2020_United_States_Senate_election_in_Iowa

2020 United States Senate election in Iowa
	Ernst: 40–50% 50–60% 60–70% 70–80% 80–90% >90%; Greenfield: 40–50% 50–60% 60–70% 70–80% 80–90% >90%; Tie: 40–50%
U.S. senator before election; Joni Ernst; Republican	Elected U.S. Senator ; Joni Ernst; Republican

2020 United States Senate election in Iowa

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The 2020 United States Senate election in Iowa was held on November 3, 2020, to elect a member of the United States Senate to represent the State of Iowa, concurrently with the 2020 U.S. presidential election, as well as other elections to the United States Senate in other states and elections to the United States House of Representatives and various state and local elections. Primaries were held on June 2.^[1]

Quick Facts Nominee, Party ...

Most experts and pollsters considered this race and the concurrent presidential race as a tossup due to incumbent president Donald Trump's low approval ratings and Ernst's own popularity dropping in polls, partly due to a viral moment in a debate where she did not know the price of corn.^[2] Despite this, Ernst was reelected by a larger-than-expected 6.6 points, while Trump simultaneously won the state with a similarly unexpected margin of victory. Ernst carried an overwhelming majority of the state's counties including many rural ones, while Greenfield carried only eight counties: Polk, Linn, Scott, Johnson, Black Hawk, Story, Cerro Gordo and Jefferson.^[3]

Despite Ernst's win, the election marked the worst Republican performance in the Class II seat since 1978, and the best Democratic performance since Tom Harkin's landslide victory in 2008. It is also the closest election since 1996.

General election

Major media described the campaign as one of the most likely to decide control of the Senate after the 2020 election.^[58]^[59] Polls conducted after the primary showed a close contest between Greenfield and Ernst, with neither candidate leading by more than 4 points.^[60]^[61]^[62]^[63]

Through June 2020, Greenfield had raised $11.5 million, compared to $14.6 million for Ernst but by September, Greenfield had pulled ahead, raising $40.0 million compared to $21.6 million for Ernst.^[64]^[65]^[66] The race was expected to be the most expensive in the state's history,^[67] and the second most expensive Senate race in the United States, after the 2020 United States Senate election in North Carolina, where Cal Cunningham challenged Thom Tillis.^[68]

Results

State senate district results

More information Party, Candidate ...

More information By county, County ...

By county

County^[100]	Joni Ernst Republican		Theresa Greenfield Democratic		Rick Stewart Libertarian		Suzanne Herzog Independent		Write-in		Margin		Total votes
County^[100]	#	%	#	%	#	%	#	%	#	%	#	%	Total votes
Adair	2,809	67.78	1,207	29.13	89	2.15	36	0.87	3	0.07	1,602	38.66	4,144
Adams	1,497	69.34	594	27.51	46	2.13	19	0.88	3	0.14	903	41.82	2,159
Allamakee	4,478	61.04	2,602	35.47	175	2.39	80	1.09	1	0.01	1,876	25.57	7,336
Appanoose	4,189	65.60	1,956	30.63	168	2.63	71	1.11	2	0.03	2,233	34.97	6,386
Audubon	2,188	64.89	1,092	32.38	70	2.08	21	0.62	1	0.03	1,096	32.50	3,372
Benton	8,830	60.93	5,202	35.90	331	2.28	120	0.83	9	0.06	3,628	25.03	14,492
Black Hawk	29,222	44.27	34,963	52.96	1,301	1.97	490	0.74	37	0.06	-5,741	-8.70	66,013
Boone	8,315	54.74	6,316	41.58	385	2.53	167	1.10	7	0.05	1,999	13.16	15,190
Bremer	8,196	56.72	5,911	40.91	254	1.76	84	0.58	5	0.03	2,285	15.81	14,450
Buchanan	6,063	56.64	4,292	40.10	248	2.32	96	0.90	5	0.05	1,771	16.55	10,704
Buena Vista	4,724	59.09	3,022	37.80	166	2.08	75	0.94	7	0.09	1,702	21.29	7,994
Butler	5,291	66.06	2,474	30.89	173	2.16	69	0.86	2	0.02	2,817	35.17	8,009
Calhoun	3,513	67.40	1,531	29.37	129	2.48	32	0.61	7	0.13	1,982	38.03	5,212
Carroll	7,245	64.91	3,580	32.07	230	2.06	96	0.86	11	0.10	3,665	32.83	11,162
Cass	4,725	65.95	2,259	31.53	120	1.67	54	0.75	7	0.10	2,466	34.42	7,165
Cedar	5,935	56.30	4,300	40.79	226	2.14	74	0.70	6	0.06	1,635	15.51	10,541
Cerro Gordo	11,339	48.19	11,534	49.02	430	1.83	211	0.90	16	0.07	-195	-0.83	23,530
Cherokee	4,214	65.59	2,002	31.16	138	2.15	67	1.04	4	0.06	2,212	34.43	6,425
Chickasaw	4,024	61.16	2,324	35.32	159	2.42	71	1.08	2	0.03	1,700	25.84	6,580
Clarke	2,906	63.05	1,520	32.98	119	2.58	60	1.30	4	0.09	1,386	30.07	4,609
Clay	5,716	64.46	2,861	32.26	193	2.18	89	1.00	9	0.10	2,855	32.19	8,868
Clayton	5,845	61.37	3,434	36.06	157	1.65	82	0.86	6	0.06	2,411	25.31	9,524
Clinton	12,559	51.57	10,942	44.93	635	2.61	200	0.82	15	0.06	1,617	6.64	24,351
Crawford	4,424	63.12	2,336	33.33	160	2.28	80	1.14	9	0.13	2,088	29.79	7,009
Dallas	28,727	51.69	25,427	45.75	1,006	1.81	381	0.69	33	0.06	3,300	5.94	55,574
Davis	2,728	67.51	1,167	28.88	112	2.77	32	0.79	2	0.05	1,561	38.63	4,041
Decatur	2,439	65.21	1,165	31.15	90	2.41	43	1.15	3	0.08	1,274	34.06	3,740
Delaware	6,454	64.96	3,235	32.56	172	1.73	71	0.71	4	0.04	3,219	32.40	9,936
Des Moines	9,468	48.27	9,296	47.39	591	3.01	232	1.18	29	0.15	172	0.88	19,616
Dickinson	7,149	63.92	3,791	33.90	174	1.56	66	0.59	4	0.04	3,358	30.03	11,184
Dubuque	26,034	49.05	25,433	47.91	1,148	2.16	428	0.81	37	0.07	601	1.13	53,080
Emmet	2,965	61.81	1,637	34.13	147	3.06	47	0.98	1	0.02	1,328	27.68	4,797
Fayette	5,865	58.06	3,912	38.73	229	2.27	89	0.88	7	0.07	1,953	19.33	10,102
Floyd	4,181	52.45	3,498	43.88	187	2.35	98	1.23	8	0.10	683	8.57	7,972
Franklin	3,270	64.55	1,639	32.35	100	1.97	50	0.99	7	0.14	1,631	32.20	5,066
Fremont	2,563	67.31	1,099	28.86	89	2.34	56	1.47	1	0.03	1,464	38.45	3,808
Greene	3,063	61.36	1,784	35.74	104	2.08	39	0.78	2	0.04	1,279	25.62	4,992
Grundy	4,900	67.90	2,120	29.38	154	2.13	38	0.53	5	0.07	2,780	38.52	7,217
Guthrie	4,103	64.86	2,000	31.62	162	2.56	56	0.89	5	0.08	2,103	33.24	6,326
Hamilton	4,679	59.42	2,913	36.99	190	2.41	84	1.07	9	0.11	1,766	22.43	7,875
Hancock	4,004	65.86	1,881	30.94	130	2.14	60	0.99	5	0.08	2,123	34.92	6,080
Hardin	5,639	63.80	2,920	33.04	195	2.21	84	0.95	1	0.01	2,719	30.76	8,839
Harrison	5,059	63.10	2,574	32.10	253	3.16	118	1.47	14	0.17	2,485	30.99	8,018
Henry	5,875	60.12	3,457	35.38	310	3.17	116	1.19	14	0.14	2,418	24.74	9,772
Howard	2,716	55.36	2,014	41.05	118	2.41	58	1.18	0	0.00	702	14.31	4,906
Humboldt	3,671	69.74	1,443	27.41	108	2.05	40	0.76	2	0.04	2,228	42.33	5,264
Ida	2,757	72.23	964	25.26	66	1.73	28	0.73	2	0.05	1,793	46.97	3,817
Iowa	5,794	60.13	3,541	36.75	205	2.13	84	0.87	11	0.11	2,253	23.38	9,635
Jackson	6,175	56.58	4,249	38.94	366	3.35	118	1.08	5	0.05	1,926	17.65	10,913
Jasper	11,405	56.95	7,905	39.47	531	2.65	167	0.83	18	0.09	3,500	17.48	20,026
Jefferson	4,008	45.50	4,547	51.62	163	1.85	80	0.91	10	0.11	-539	-6.12	8,808
Johnson	23,773	28.77	57,063	69.06	1,382	1.67	373	0.45	42	0.05	-33,290	-40.29	82,633
Jones	6,320	57.97	4,237	38.86	273	2.50	68	0.62	4	0.04	2,083	19.11	10,902
Keokuk	3,565	68.39	1,489	28.56	101	1.94	53	1.02	5	0.10	2,076	39.82	5,213
Kossuth	5,957	66.14	2,799	31.08	193	2.14	57	0.63	0	0.00	3,158	35.07	9,006
Lee	8,489	51.29	7,445	44.98	485	2.93	122	0.74	11	0.07	1,044	6.31	16,552
Linn	53,248	42.10	69,125	54.66	3,188	2.52	815	0.64	90	0.07	-15,877	-12.55	126,466
Louisa	3,259	61.97	1,804	34.30	141	2.68	51	0.97	4	0.08	1,455	27.67	5,259
Lucas	3,105	68.32	1,302	28.65	99	2.18	36	0.79	3	0.07	1,803	39.67	4,545
Lyon	5,522	81.80	1,073	15.89	104	1.54	50	0.74	2	0.03	4,449	65.90	6,751
Madison	6,245	64.25	3,168	32.59	218	2.24	86	0.88	3	0.03	3,077	31.66	9,720
Mahaska	7,860	70.00	2,969	26.44	273	2.43	118	1.05	8	0.07	4,891	43.56	11,228
Marion	12,211	64.06	6,269	32.89	423	2.22	144	0.76	15	0.08	5,942	31.17	19,062
Marshall	9,057	50.68	8,187	45.81	442	2.47	165	0.92	21	0.12	870	4.87	17,872
Mills	5,347	65.54	2,544	31.18	177	2.17	82	1.01	8	0.10	2,803	34.36	8,158
Mitchell	3,347	57.69	2,282	39.33	124	2.14	49	0.84	0	0.00	1,065	18.36	5,802
Monona	3,054	65.47	1,455	31.19	108	2.32	39	0.84	9	0.19	1,599	34.28	4,665
Monroe	2,742	68.40	1,148	28.64	84	2.10	34	0.85	1	0.02	1,594	39.76	4,009
Montgomery	3,633	68.53	1,520	28.67	98	1.85	46	0.87	4	0.08	2,113	39.86	5,301
Muscatine	10,278	50.28	9,381	45.89	570	2.79	199	0.97	13	0.06	897	4.39	20,441
O'Brien	5,675	76.05	1,640	21.98	105	1.41	38	0.51	4	0.05	4,035	54.07	7,462
Osceola	2,525	77.38	657	20.13	49	1.50	31	0.95	1	0.03	1,868	57.25	3,263
Page	5,152	69.27	2,067	27.79	138	1.86	78	1.05	3	0.04	3,085	41.48	7,438
Palo Alto	3,113	63.12	1,677	34.00	106	2.15	36	0.73	0	0.00	1,436	29.12	4,932
Plymouth	10,145	72.26	3,587	25.55	219	1.56	77	0.55	11	0.08	6,558	46.71	14,039
Pocahontas	2,641	69.87	1,003	26.53	91	2.41	39	1.03	6	0.16	1,638	43.33	3,780
Polk	106,443	41.54	142,328	55.54	5,313	2.07	1,985	0.77	188	0.07	-35,885	-14.00	256,257
Pottawattamie	24,720	54.85	18,520	41.10	1,269	2.82	524	1.16	32	0.07	6,200	13.76	45,065
Poweshiek	5,361	53.38	4,381	43.62	202	2.01	91	0.91	8	0.08	980	9.76	10,043
Ringgold	1,870	69.36	732	27.15	75	2.78	16	0.59	3	0.11	1,138	42.21	2,696
Sac	3,849	70.17	1,440	26.25	129	2.35	60	1.09	7	0.13	2,409	43.92	5,485
Scott	42,941	46.88	45,751	49.94	2,139	2.33	709	0.77	66	0.07	-2,810	-3.07	91,606
Shelby	4,489	67.06	1,989	29.71	156	2.33	57	0.85	3	0.04	2,500	37.35	6,694
Sioux	15,785	83.54	2,828	14.97	192	1.02	81	0.43	9	0.05	12,957	68.57	18,895
Story	20,750	41.08	28,216	55.86	1,133	2.24	370	0.73	44	0.09	-7,466	-14.78	50,513
Tama	5,090	56.74	3,588	40.00	205	2.29	79	0.88	8	0.09	1,502	16.74	8,970
Taylor	2,337	72.80	762	23.74	83	2.59	28	0.87	0	0.00	1,575	49.07	3,210
Union	3,820	62.38	2,051	33.49	172	2.81	76	1.24	5	0.08	1,769	28.89	6,124
Van Buren	2,583	68.84	1,065	28.38	75	2.00	28	0.75	1	0.03	1,518	40.46	3,752
Wapello	8,464	55.15	6,344	41.33	394	2.57	132	0.86	14	0.09	2,120	13.81	15,348
Warren	17,276	56.27	12,478	40.64	692	2.25	234	0.76	23	0.07	4,798	15.63	30,703
Washington	6,773	58.12	4,519	38.78	262	2.25	95	0.82	5	0.04	2,254	19.34	11,654
Wayne	2,186	71.55	784	25.66	53	1.73	28	0.92	4	0.13	1,402	45.89	3,055
Webster	10,195	57.81	6,845	38.81	403	2.29	173	0.98	19	0.11	3,350	19.00	17,635
Winnebago	3,336	56.29	2,361	39.84	153	2.58	72	1.21	4	0.07	975	16.45	5,926
Winneshiek	6,039	50.49	5,581	46.66	218	1.82	118	0.99	4	0.03	458	3.83	11,960
Woodbury	24,175	54.27	18,674	41.92	994	2.23	629	1.41	72	0.16	5,501	12.35	44,544
Worth	2,425	55.40	1,803	41.19	98	2.24	46	1.05	5	0.11	622	14.21	4,377
Wright	3,889	62.85	2,063	33.34	158	2.55	76	1.23	2	0.03	1,826	29.51	6,188
Totals	864,997	51.74	754,859	45.15	36,961	2.21	13,800	0.83	1,211	0.07	110,138	6.59	1,671,828

Counties that flipped from Democratic to Republican

Clinton (largest municipality: Clinton)
Des Moines (largest municipality: Burlington)
Dubuque (largest municipality: Dubuque)
Floyd (largest municipality: Charles City)
Howard (largest municipality: Cresco)
Lee (largest municipality: Fort Madison)
Worth (largest municipality: Northwood)

Counties that flipped from Republican to Democratic

Scott (largest municipality: Davenport)

More information By congressional district, District ...

Notes

Partisan clients

Poll sponsored by The Center for American Greatness, a pro-Trump organization.
Poll sponsored by The American Action Forum, which is a 501 organization which usually supports Republican candidates.
Poll sponsored by The Human Rights Campaign, which has endorsed Biden prior to this poll's sampling period.
Poll sponsored by AARP.
This poll's sponsor is the American Principles Project, a 501 that supports the Republican Party.
Poll sponsored by the End Citizens United, which has only supported Democratic candidates who are against the landmark Citizens United Supreme Court ruling.
Poll sponsored by Emily's List, an organization that supports Democratic female candidates.
Poll sponsored by the Eddie Mauro campaign
Poll sponsored by Save My Care, a pro-Affordable Care Act organisation

Voter samples

Key:
A – all adults
RV – registered voters
LV – likely voters
V – unclear
Calculated by taking the difference of 100% and all other candidates combined.
Stewart (L) with 2%; "Don't recall" and Undecided with 1%; Herzog (I) and would not vote with 0%
Stewart (L) and Undecided with 1%; Herzog (I) and "Someone else" with 0%
Herzog (I) with 3%; Stewart (L) with 2%; "Other candidate or write-in" with 1%
With voters who lean towards a given candidate
"Someone else" with 2%
Herzog (I) and Stewart (L) with 1%; Undecided with 3%
"Refused" with 4%; "Someone else" and "Undecided/do not remember" with 3%; would not vote with 1%
"Someone else" with 1%; Undecided with 4%
"Someone else" with 3%
Standard VI response
"Someone else" with 3%; Undecided with 7%
Results generated with high Democratic turnout model
Results generated with high Republican turnout model
Herzog (I) and Stewart (L) with 2%; "Someone else" and would not vote with 1%; "Undecided/Refused" with 6%
Stewart (L) with 5%; Herzog (I) with 0%; Undecided with 3%
Herzog (I), "No one" and Stewart (L) with 1%; "Other" with 0%; Undecided with 2%
With a likely voter turnout model featuring higher turnout than in the 2016 presidential election
With a likely voter turnout model featuring lower turnout than in the 2016 presidential election
Stewart (L) with 2%; Herzog (I) with 1%; "Other" with 0%; Undecided with 6%
"Someone else" with 2%; Undecided with 8%
Would not vote with 1%; "Someone else" with 0%; "Undecided/Refused" with 4%
Stewart (L) with 2%; Herzog (I) with 1%; "Someone else" with 0%; Undecided with 3%
Herzog (I) and Stewart (L) with 1%; Undecided with 12%
If the only candidates were Ernst and Greenfield
Undecided with 9%
Stewart (L) with 1%; Herzog (I), "Other" and "No one" with 0%; Undecided with 4%
Stewart (L) with 1; Herzog (I) with 0%; Undecided with 4%
Herzog (I) and Stewart (L) with 2%; would not vote with 1%; "someone else" with 0%; "Undecided/Refused" with 14%
"Someone else" with 3%; would not vote with 2%; Undecided with 7%
Would not vote with 1%; Undecided with 4%
Would not vote with 1%; Undecided with 7%
Undecided with 8%
Stewart (L) with 2%; Herzog (I) with 1%; Undecided with 3%
Stewart (L) and Undecided with 2%; Herzog (I) with 1%
"No one" with 11%
Undecided with 24%
"Another candidate" with 6%; Undecided with 7%
Response after pollster addresses respondents with talking points about Ernst and Mauro
Would not vote with 3%
"Would consider voting for someone else" with 20%; "unsure" with 6%

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[InsiderAdv-106] Poll sponsored by The Center for American Greatness, a pro-Trump organization.

[americanaction-122] Poll sponsored by The American Action Forum, which is a 501 organization which usually supports Republican candidates.

[128] Poll sponsored by The Human Rights Campaign, which has endorsed Biden prior to this poll's sampling period.

[AARP-133] Poll sponsored by AARP.

[141] This poll's sponsor is the American Principles Project, a 501 that supports the Republican Party.

[ECU-143] Poll sponsored by the End Citizens United, which has only supported Democratic candidates who are against the landmark Citizens United Supreme Court ruling.

[144] Poll sponsored by Emily's List, an organization that supports Democratic female candidates.

[Mauro-145] Poll sponsored by the Eddie Mauro campaign

[SMC-147] Poll sponsored by Save My Care, a pro-Affordable Care Act organisation

[Key-56] Key:
A – all adults
RV – registered voters
LV – likely voters
V – unclear

[100] Calculated by taking the difference of 100% and all other candidates combined.

[101] Stewart (L) with 2%; "Don't recall" and Undecided with 1%; Herzog (I) and would not vote with 0%

[102] Stewart (L) and Undecided with 1%; Herzog (I) and "Someone else" with 0%

[103] Herzog (I) with 3%; Stewart (L) with 2%; "Other candidate or write-in" with 1%

[lean-104] With voters who lean towards a given candidate

[105] "Someone else" with 2%

[107] Herzog (I) and Stewart (L) with 1%; Undecided with 3%

[108] "Refused" with 4%; "Someone else" and "Undecided/do not remember" with 3%; would not vote with 1%

[SE1U4-109] "Someone else" with 1%; Undecided with 4%

[110] "Someone else" with 3%

[stand4-111] Standard VI response

[SE3U7-112] "Someone else" with 3%; Undecided with 7%

[113] Results generated with high Democratic turnout model

[114] Results generated with high Republican turnout model

[115] Herzog (I) and Stewart (L) with 2%; "Someone else" and would not vote with 1%; "Undecided/Refused" with 6%

[116] Stewart (L) with 5%; Herzog (I) with 0%; Undecided with 3%

[117] Herzog (I), "No one" and Stewart (L) with 1%; "Other" with 0%; Undecided with 2%

[High-118] With a likely voter turnout model featuring higher turnout than in the 2016 presidential election

[Low-119] With a likely voter turnout model featuring lower turnout than in the 2016 presidential election

[120] Stewart (L) with 2%; Herzog (I) with 1%; "Other" with 0%; Undecided with 6%

[121] "Someone else" with 2%; Undecided with 8%

[123] Would not vote with 1%; "Someone else" with 0%; "Undecided/Refused" with 4%

[124] Stewart (L) with 2%; Herzog (I) with 1%; "Someone else" with 0%; Undecided with 3%

[125] Herzog (I) and Stewart (L) with 1%; Undecided with 12%

[126] If the only candidates were Ernst and Greenfield

[127] Undecided with 9%

[129] Stewart (L) with 1%; Herzog (I), "Other" and "No one" with 0%; Undecided with 4%

[SL1HI0U4-130] Stewart (L) with 1; Herzog (I) with 0%; Undecided with 4%

[131] Herzog (I) and Stewart (L) with 2%; would not vote with 1%; "someone else" with 0%; "Undecided/Refused" with 14%

[132] "Someone else" with 3%; would not vote with 2%; Undecided with 7%

[134] Would not vote with 1%; Undecided with 4%

[135] Would not vote with 1%; Undecided with 7%

[136] Undecided with 8%

[SL2HI1U3-137] Stewart (L) with 2%; Herzog (I) with 1%; Undecided with 3%

[138] Stewart (L) and Undecided with 2%; Herzog (I) with 1%

[139] "No one" with 11%

[140] Undecided with 24%

[142] "Another candidate" with 6%; Undecided with 7%

[146] Response after pollster addresses respondents with talking points about Ernst and Mauro

[148] Would not vote with 3%

[149] "Would consider voting for someone else" with 20%; "unsure" with 6%

[1] [1]
"United States Senate election in Iowa, 2020 (June 2 Democratic primary)". ballotpedia.org. Retrieved January 13, 2020.

[2] [2]
Rosenberg, Benjamin (October 16, 2020). "Joni Ernst didn't know the price of soybeans. Here's why that could cost her". Vox. Retrieved May 25, 2023.

[3] [3]
"United States Senate election in Iowa, 2020 (General Election)".

[4] [4]
Cohen, Zach C. (December 5, 2018). "How 2014's Outsiders Became 2020's Insiders". National Journal. Archived from the original on July 9, 2019. Retrieved December 5, 2018.

[5] [5]
Axelrod, Tal (December 8, 2018). "Iowa's Ernst will run for reelection in 2020". TheHill. Retrieved December 30, 2018.

[:1-6] [6]
Gunzburger, Ron. "Politics1 – Online Guide to Iowa Politics". politics1.com. Retrieved December 31, 2018.

[7] [7]
Tope, Mallory (October 31, 2019). "Candidates gear up campaigns for Iowa U.S. Senate race". Iowa State Daily. Archived from the original on September 13, 2020. Retrieved May 15, 2020.

[IA2020-8] [8]
"Primary Election". sos.iowa.gov.

[auto18-9] [9]
"2020 Candidates". maggieslist.org.

[IAsosr-10] [10]
"Primary Election – 2020 CANVASS SUMMARY" (PDF). Iowa Secretary of State. Retrieved August 27, 2020.

[11] [11]
"State of Iowa 2020 Primary Election Results". The Des Moines Register. June 3, 2020. Retrieved September 5, 2020.

[bi_primary-12] [12]
Panetta, Grace. "Theresa Greenfield wins the Democratic primary for US Senate in Iowa". Business Insider. Retrieved August 24, 2020.

[13] [13]
Manchester, Julia (June 2, 2020). "Greenfield wins Senate Democratic primary in Iowa". The Hill. Retrieved September 14, 2020.

[14] [14]
Pfannenstiel, Brianne. "Theresa Greenfield to take on Joni Ernst in high-profile battle for U.S. Senate seat". Des Moines Register. Retrieved August 7, 2020.

[15] [15]
"Democrats Fight for Chance to Take on GOP Sen. Ernst in Iowa". The New York Times. The Associated Press. June 1, 2020. ISSN 0362-4331. Retrieved June 7, 2020.

[16] [16]
Gerber, Drew [@dagerber] (June 3, 2019). "Theresa Greenfield launches her campaign for #IASEN. She's been highly sought after by the party" (Tweet). Retrieved June 3, 2019 – via Twitter.

[17] [17]
Pfannenstiel, Brianne (August 26, 2019). "Retired Navy Admiral Michael Franken to run for U.S. Senate, challenge Joni Ernst". Des Moines Register. Retrieved August 26, 2019.

[18] [18]
Becker, Amanda; Jackson, Katharine (January 19, 2019). "Women protest in hundreds of U.S. cities for third straight year". Reuters. Retrieved May 11, 2019.

[19] [19]
Wade, Jazmen (July 20, 2019). "Iowa US Senate Candidate Kimberly Graham for the People". KHQA.

[20] [20]
Iowa Starting Line [@IAStartingLine] (May 19, 2019). "Guess we'll wait for the official thing tomorrow AM, but FYI #IASenpic.twitter.com/E0EJWVXsRF" (Tweet). Retrieved May 19, 2019 – via Twitter.

[21] [21]
Rivers, Amie (March 2, 2020). "U.S. Senate candidate Cal Woods looking to take on 'climate crisis' if elected". The Courier.

[22] [22]
"Meet Cal". Cal for Iowa. Archived from the original on April 10, 2020. Retrieved April 10, 2020.

[23] [23]
Lynch, James Q. "Cal Woods drops out of Iowa Democratic U.S. Senate race". The Gazette. Retrieved May 5, 2020.

[24] [24]
Price, Dave [@idaveprice] (April 30, 2019). "Confirmed: Iowa Democrat @RepCindyAxne running for re-election in the 3rd District. Not running for senate against @SenJoniErnst in 2020. Axne is in her first term after defeating two term incumbent @RepDavidYoung in 2018. @WHOhd #iowavotes2020" (Tweet). Retrieved April 30, 2019 – via Twitter.

[25] [25]
"2020 Senate At-A-Glance" (PDF). Cook Political Report. Retrieved January 9, 2019.

[:0-26] [26]
"Democrats look to unseat Joni Ernst in 2020 Senate race". The Washington Times. Retrieved December 28, 2018.

[27] [27]
Bowman, Bridget (August 21, 2019). "House freshmen try to keep it local as presidential race steals the spotlight". Roll Call. Retrieved August 22, 2019.

[Meyer-28] [28]
Meyer, Elizabeth (September 24, 2019). "Finkenauer Endorses Greenfield In Effort To Unseat Ernst". Iowa Starting Line.

[Endorsement_Alert!-29] [29]
"Endorsement Alert!". us7.campaign-archive.com. Retrieved August 30, 2019.

[auto1-30] [30]
"Who will run against Joni Ernst in 2020?". Iowa Starting Line. November 12, 2018. Retrieved November 12, 2018.

[31] [31]
Arkin, James (February 27, 2019). "Senate recruiting notebook: Duran clarifies field facing Gardner". Politico. Retrieved February 27, 2019. And former state Sen. Rita Hart, the 2018 Democratic nominee for lieutenant governor, is a potential candidate, according to multiple Iowa Democrats, but she has not discussed a campaign publicly.

[32] [32]
Weig, Nick (February 26, 2019). "Sen. Liz Mathis meets with Democrats in D.C. to talk about 2020 Senate race". CBS2. Retrieved February 27, 2019.

[IASLFeb-33] [33]
Rynard, Pat (February 25, 2019). "Who's Gearing Up To Challenge Joni Ernst?". Iowa Starting Line. Retrieved February 25, 2019.

[34] [34]
Judd, Donald (August 5, 2019). "Iowa native JD Scholten announces second bid to unseat GOP Rep. Steve King". CNN. Retrieved August 5, 2019.

[35] [35]
Pfannenstiel, Brianne (February 22, 2019). "Former Iowa Gov. Tom Vilsack will not run for the U.S. Senate against Sen. Joni Ernst in 2020". Des Moines Register. Retrieved February 22, 2019.

[36] [36]
"Stacey Walker won't seek U.S. Senate nomination". The Gazette. August 12, 2019. Retrieved August 12, 2019.

[Lynch-37] [37]
Lynch, James Q. "Linn County Supervisor Stacey Walker endorses Kimberly Graham for Senate". The Gazette. Retrieved October 30, 2019.

[:02-38] [38]
"Iowa Press Debates: U.S. Senate Democratic Primary". www.youtube.com.

[39] [39]
"The Public Pulse: Davis essay rang true; Hagel supports Franken; Trump is the real threat". Omaha.com. May 28, 2020.

[kimberly_graham_endorsements_list-40] [40]
"Endorsements". Kimberly Graham for U.S. Senate. Retrieved April 2, 2020.

[41] [41]
"Kimberly Graham". Brand New Congress. October 23, 2019. Archived from the original on October 29, 2019. Retrieved October 29, 2019.

[42] [42]
Murray, Isabella (December 5, 2019). "Iowa Climate Strikes Will Draw National, State Political Leaders". Iowa Starting Line.

[auto10-43] [43]
"IA-Sen: Sen. Sherrod Brown (D. OH) Helps Theresa Greenfield (D) Get Ready To Defeat Joni Ernst (R)". Daily KOS. December 16, 2019.

[Greenfield-44] [44]
"Endorsements". greenfieldforiowa.com. Archived from the original on May 7, 2020. Retrieved May 9, 2020.

[auto11-45] [45]
Opsahl, Robin (June 25, 2019). "Theresa Greenfield nets endorsement from Rep. Dave Loebsack in Democratic Senate primary". Des Moines Register.

[46] [46]
Obama, Barack (August 3, 2020). "First Wave of 2020 Endorsements". medium.com. Retrieved September 7, 2020.

[auto5-47] [47]
Brown, Kris (January 8, 2020). "Brady Endorses Theresa Greenfield for U.S. Senate: Iowa Needs A Common-sense Champion". Brady.

[auto7-48] [48]
"DSCC Endorses Theresa Greenfield in Iowa Senate Campaign". DSCC: Democratic Senatorial Campaign Committee. June 6, 2019.

[auto9-49] [49]
"EMILY's List Endorses Theresa Greenfield for U.S. Senate in Iowa". Emily's List. June 6, 2019.

[auto12-50] [50]
Muller, Tiffany (July 10, 2019). "End Citizens United Endorses Theresa Greenfield; Names Ernst to "Big Money 20"". End Citizens United.

[auto14-51] [51]
"2020 – Feminist Majority PAC". feministmajoritypac.org.

[auto13-52] [52]
"In Key Senate Races, Giffords Backs Challengers in Iowa and North Carolina Taking on NRA-Backed Incumbents". Giffords. April 10, 2020.

[auto4-53] [53]
Burke, Holly (October 2, 2019). "LCV Action Fund Endorses Theresa Greenfield for U.S. Senate". League of Conservation Voters. Retrieved November 26, 2019.

[auto19-54] [54]
"NARAL Pro-Choice America Endorses Theresa Greenfield for U.S. Senate". NARAL Pro-Choice America. November 7, 2019.

[auto3-55] [55]
"2020 Endorsements". Population Connection. Archived from the original on September 18, 2020. Retrieved May 9, 2020.

[57] [56]
"The Green Papers: Iowa 2020 General Election". The Green Papers. May 15, 2020. Retrieved May 15, 2020.

[58] [57]
"Suzanne Herzog For US Senate – Iowa's Independent Voice". Archived from the original on December 16, 2019. Retrieved December 16, 2019.

[59] [58]
Phillips, Amber (August 7, 2020). "The most competitive Senate races of 2020". The Washington Post. Retrieved September 19, 2020.

[60] [59]
Nilsen, Ella (September 14, 2020). "The ways Democrats could retake the Senate majority, explained". Vox. Retrieved September 19, 2020.

[61] [60]
"Iowa Senate – Ernst vs. Greenfield". RealClear Politics. Retrieved September 5, 2020.

[62] [61]
"Iowa U.S. Senate Polls". FiveThirtyEight. June 28, 2018. Retrieved September 5, 2020.

[63] [62]
Pfannenstiel, Brianne (June 13, 2020). "Iowa Poll: Theresa Greenfield leads Joni Ernst in tight race for U.S. Senate". The Des Moines Register. Retrieved September 5, 2020.

[64] [63]
"IOWA: CLOSE CONTESTS FOR PREZ & SENATE" (Press release). West Long Branch, NJ: Monmouth University. August 5, 2020. Retrieved September 5, 2020.

[65] [64]
Panetta, Grace (August 7, 2020). "What you need to know about the US Senate election in Iowa between Joni Ernst and Theresa Greenfield". Business Insider. Retrieved September 5, 2020.

[66] [65]
Coltrain, Nick. "Record-smashing Iowa Senate race fuels deluge of final-stretch campaign spending". Des Moines Register.

[67] [66]
"Iowa Senate 2020 Race". OpenSecrets.

[68] [67]
Gabriel, Trip (September 2, 2020). "Joni Ernst, in a Tight Senate Race, Repeats a Debunked Coronavirus Theory". The New York Times. Retrieved September 7, 2020.

[69] [68]
Pfannenstiel, Brianne. "In a slew of competitive Senate races, Iowa's draws second-highest advertising spending in the country". Des Moines Register. Retrieved September 22, 2020.

[70] [69]
"Iowa Press Debates: U.S. Senate". Iowa Press Debates. September 28, 2020. Archived from the original on October 20, 2020. Retrieved October 15, 2020.

[Cook_PR-71] [70]
"2020 Senate Race Ratings for October 29, 2020". The Cook Political Report. Retrieved March 11, 2021.

[Inside_Elections-72] [71]
"2020 Senate Ratings". Senate Ratings. The Rothenberg Political Report. Retrieved March 11, 2021.

[Sabato's_Crystal_Ball-73] [72]
"2020 Senate race ratings". Sabato's Crystal Ball. Retrieved March 12, 2021.

[Politico-74] [73]
"2020 Election Forecast". Politico. Retrieved October 21, 2020.

[Daily_Kos-75] [74]
"2020 Senate Race Ratings". Daily Kos Elections. Retrieved March 13, 2021.

[RCP-76] [75]
"Battle for the Senate 2020". RCP. October 23, 2020.

[DDHQ-77] [76]
"2020 Senate Elections Model". Decision Desk HQ. September 2, 2020. Retrieved October 21, 2020.

[78] [77]
Silver, Nate (August 12, 2020). "Forecasting the race for the Senate". FiveThirtyEight. Retrieved October 21, 2020.

[79] [78]
"Forecasting the US elections". The Economist. November 2, 2020. Retrieved March 13, 2021.

[80] [79]
"Endorsed Candidates". www.cwfpac.com. Campaign for Working Families. Retrieved August 26, 2020.

[81] [80]
PAC, Huck. "Candidates – Huck PAC". www.huckpac.com.

[82] [81]
Kirsten Gillibrand (February 5, 2020). "Off the Sidelines Endorsed Candidates".

[83] [82]
"First Wave of 2020 Endorsements". August 3, 2020.

[84] [83]
"Endorsements | Warren Democrats". elizabethwarren.com. Archived from the original on January 7, 2021. Retrieved November 1, 2020.

[85] [84]
"U.S. Senate – Education Votes". educationvotes.nea.org.

[86] [85]
"Iowa – Official UAW Endorsements". uawendorsements.org. United Automobile Workers.

[87] [86]
"Cedar Rapids Gazette Editorial Board Endorses Greenfield: "It's time for a new voice in the Senate, that voice is Theresa Greenfield."". October 3, 2020. Archived from the original on November 13, 2020. Retrieved October 31, 2020.

[88] [87]
"Des Moines Register Editorial Board Endorsement: "Greenfield should be given an opportunity to refocus the junior senator's office on working Iowans" – Theresa Greenfield". Theresa Greenfield. October 18, 2020. Archived from the original on November 1, 2020. Retrieved October 31, 2020.

[89] [88]
"Telegraph Herald Editorial Board: "Greenfield merits opportunity to serve Iowa in U.S. Senate"". October 25, 2020. Archived from the original on November 3, 2020. Retrieved October 31, 2020.

[90] [89]
"Our pick: Send Theresa Greenfield and Rita Hart to Congress".

[91] [90]
"Quad-City Times Editorial Board: "We endorse Theresa Greenfield for U.S. Senate."". October 9, 2020. Archived from the original on October 21, 2020. Retrieved October 31, 2020.

[92] [91]
"2020 Endorsements".

[93] [92]
"Theresa Greenfield". Climate Hawks Vote.

[94] [93]
"Theresa Greenfield for Senate (D-IA) – Council for a Livable World". Council for a Livable World.

[95] [94]
"Democracy for America endorses Theresa Greenfield for U.S. Senate in Iowa". Democracy for America. February 12, 2020.

[96] [95]
"Everytown For Gun Safety Action Fund Endorses Theresa Greenfield for U.S. Senate in Iowa". Everytown. June 9, 2020.

[97] [96]
"JStreetPAC Candidates". JStreetPAC. Archived from the original on May 2, 2018. Retrieved November 1, 2020.

[98] [97]
"Candidates We Endorse and Support". NCPSSM.

[99] [98]
"NRDC Action Fund Endorses 11 House, Senate Candidates". nrdcactionfund.org. June 15, 2020.

[generalcanvass-150] [99]
"General Election – 2020 Canvass Summary" (PDF). Iowa Secretary of State.

[151] [100]
"Iowa U.S. Senate Election Results". The New York Times. November 3, 2020. ISSN 0362-4331. Retrieved October 3, 2021.

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[lower-alpha 2]

Party		Candidate	Votes	%
	Republican	Joni Ernst (incumbent)	226,589	98.64%
	Republican	Write-In	3,132	1.36%
Total votes			229,721	100.00%

Host network	Date	Link(s)	Participants
Host network	Date	Link(s)	Theresa Greenfield	Michael T. Franken	Kimberly Graham	Eddie Mauro
Iowa PBS	May 18, 2020	^[38]	Present	Present	Present	Present

Poll source	Date(s) administered	Sample size^{[lower-alpha 1]}	Margin of error	Michael Franken	Kimberly Graham	Theresa Greenfield	Eddie Mauro	Undecided
Public Policy Polling	May 5–6, 2020	849 (V)	–	12%	4%	43%	4%	36%
Emerson College	October 13–16, 2019	317 (LV)	± 5.5%	6%	4%	11%	6%	74%

Party		Candidate	Votes	%
	Democratic	Theresa Greenfield	132,001	47.71%
	Democratic	Michael T. Franken	68,851	24.88%
	Democratic	Kimberly Graham	41,554	15.02%
	Democratic	Eddie Mauro	30,400	10.99%
	Democratic	Cal Woods (withdrawn)	3,372	1.21%
	Democratic	Write-In	514	0.19%
Total votes			276,692	100.00%

Host	Date & time	Link(s)	Participants
Host	Date & time	Link(s)	Joni Ernst (R)	Theresa Greenfield (D)
Iowa Press Debates	September 28, 2020	^[69]	Present	Present

2020_United_States_Senate_election_in_Iowa

2020 United States Senate election in Iowa

Republican primary

Candidates

Nominee

Withdrawn

Endorsements

Result

Democratic primary

Candidates

Nominee

Eliminated in primary

Withdrawn

Declined

Debates

Endorsements

Polling

Results

Other candidates

Libertarian Party

Nominee

Independents

Declared

General election

Debate

Predictions

Endorsements

Polling

Graphical summary

Aggregate polling

Results

See also

Notes

References

Further reading

External links

Share this article:

Source	Ranking	As of
The Cook Political Report^[70]	Tossup	October 29, 2020
Inside Elections^[71]	Tossup	October 28, 2020
Sabato's Crystal Ball^[72]	Lean R	November 2, 2020
Politico^[73]	Tossup	November 2, 2020
Daily Kos^[74]	Tossup	October 30, 2020
RCP^[75]	Tossup	October 23, 2020
DDHQ^[76]	Tossup	November 3, 2020
538^[77]	Tossup	November 2, 2020
Economist^[78]	Tossup	November 2, 2020

Theresa Greenfield vs. Joni Ernst
Source of poll aggregation	Dates administered	Dates updated	Theresa Greenfield	Joni Ernst	Other/Undecided^{[lower-alpha 2]}	Margin
Real Clear Politics	November 2, 2020	November 3, 2020	45.8%	47.2%	7.0%	Ernst +1.4
270 to Win	November 2, 2020	November 3, 2020	46.6%	47.0%	6.4%	Ernst +0.4

Poll source	Date(s) administered	Sample size^{[lower-alpha 1]}	Margin of error	Joni Ernst (R)	Theresa Greenfield (D)	Other/ Undecided
Public Policy Polling	November 1–2, 2020	871 (V)	–	47%	48%	5%
Change Research	October 29 – November 1, 2020	1,084 (LV)	± 3.2%	47%	48%	4%^{[lower-alpha 3]}
Civiqs/Daily Kos	October 29 – November 1, 2020	853 (LV)	± 3.7%	47%	50%	2%^{[lower-alpha 4]}
Data for Progress	October 27 – November 1, 2020	951 (LV)	± 3.2%	45%	49%	6%^{[lower-alpha 5]}
Emerson College	October 29–31, 2020	604 (LV)	± 3.9%	48%^{[lower-alpha 6]}	51%	2%^{[lower-alpha 7]}
InsiderAdvantage (R) Archived November 1, 2020, at the Wayback Machine^{[upper-alpha 1]}	October 30, 2020	400 (LV)	± 4.9%	51%	45%	4%^{[lower-alpha 8]}
Selzer & Co./Des Moines Register	October 26–29, 2020	814 (LV)	± 3.4%	46%	42%	11%^{[lower-alpha 9]}
Quinnipiac University	October 23–27, 2020	1,225 (LV)	± 2.8%	48%	46%	1%^{[lower-alpha 10]}
RABA Research	October 21–24, 2020	693 (LV)	± 4%	45%	51%	–
Emerson College	October 19–21, 2020	435 (LV)	± 4.7%	51%^{[lower-alpha 6]}	46%	3%^{[lower-alpha 11]}
RMG Research Archived October 31, 2020, at the Wayback Machine	October 15–21, 2020	800 (LV)	± 3.5%	43%^{[lower-alpha 12]}	46%	10%^{[lower-alpha 13]}
				41%^{[lower-alpha 14]}	48%	10%^{[lower-alpha 13]}
				45%^{[lower-alpha 15]}	45%	10%^{[lower-alpha 13]}
Siena College/NYT Upshot	October 18–20, 2020	753 (LV)	± 3.9%	45%	44%	12%^{[lower-alpha 16]}
Insider Advantage (R) Archived October 21, 2020, at the Wayback Machine^{[upper-alpha 1]}	October 18–19, 2020	400 (LV)	± 4.9%	43%	48%	8%^{[lower-alpha 17]}
Monmouth University	October 15–19, 2020	501 (RV)	± 4.4%	47%	47%	5%^{[lower-alpha 18]}
		501 (LV)^{[lower-alpha 19]}		47%	49%	–
		501 (LV)^{[lower-alpha 20]}		45%	51%	–
Data for Progress (D)	October 8–11, 2020	822 (LV)	± 3.4%	43%	47%	10%^{[lower-alpha 21]}
YouGov/CBS	October 6–9, 2020	1,022 (LV)	± 3.5%	43%	47%	10%^{[lower-alpha 22]}
Opinion Insight (R)^{[upper-alpha 2]}	October 5–8, 2020	800 (LV)	± 3.46%	47%^{[lower-alpha 6]}	45%	8%^{[lower-alpha 23]}
Civiqs/Daily Kos	October 3–6, 2020	756 (LV)	± 3.9%	46%	49%	6%^{[lower-alpha 24]}
Quinnipiac University	October 1–5, 2020	1,205 (LV)	± 2.8%	45%	50%	5%^{[lower-alpha 10]}
Data for Progress (D)	September 23–28, 2020	743 (LV)	± 3.6%	42%^{[lower-alpha 12]}	44%	14%^{[lower-alpha 25]}
Data for Progress (D)	September 23–28, 2020	743 (LV)	± 3.6%	45%^{[lower-alpha 26]}	46%	9%^{[lower-alpha 27]}
Hart Research Associates (D)^{[upper-alpha 3]}	September 24–27, 2020	400 (LV)	± 4.9%	48%	48%	–
RABA Research	September 23–26, 2020	780 (LV)	± 4%	39%	51%	–
Monmouth University	September 18–22, 2020	402 (RV)	± 4.9%	47%	47%	5%^{[lower-alpha 28]}
		402 (LV)^{[lower-alpha 19]}		46%	49%	5%^{[lower-alpha 29]}
		402 (LV)^{[lower-alpha 20]}		47%	48%	5%^{[lower-alpha 29]}
Siena College/NYT Upshot	September 16–22, 2020	501 (LV)	± 4.99%	40%	42%	19%^{[lower-alpha 30]}
Selzer/Des Moines Register	September 14–17, 2020	658 (LV)	± 3.8%	42%	45%	12%^{[lower-alpha 31]}
Fabrizio Ward/Hart Research Associates^{[upper-alpha 4]}	August 30 – September 5, 2020	800 (LV)	± 3.5%	50%	45%	5%^{[lower-alpha 32]}
Opinion Insight (R)^{[upper-alpha 2]}	August 30 – September 2, 2020	800 (LV)	± 3.46%	49%^{[lower-alpha 6]}	43%	7%^{[lower-alpha 33]}
Public Policy Polling	August 13–14, 2020	729 (V)	± 4.1%	45%	48%	8%^{[lower-alpha 34]}
Monmouth University	July 30 – August 3, 2020	401 (RV)	± 4.9%	48%	45%	6%^{[lower-alpha 35]}
		401 (LV)^{[lower-alpha 19]}		48%	47%	6%^{[lower-alpha 35]}
		401 (LV)^{[lower-alpha 20]}		48%	47%	5%^{[lower-alpha 36]}
Data for Progress	July 24 – August 2, 2020	1,101 (LV)	± 3.2%	43%	45%	11%^{[lower-alpha 37]}
RMG Research	July 27–30, 2020	500 (RV)	± 4.5%	36%	40%	24%^{[lower-alpha 38]}
Spry Strategies (R)^{[upper-alpha 5]}	July 11–16, 2020	701 (LV)	± 3.7%	43%	45%	12%^{[lower-alpha 39]}
GQR Research (D)^{[upper-alpha 6]}	June 23–28, 2020	800 (LV)	± 3.5%	47%	49%	4%
Selzer/Des Moines Register	June 7–10, 2020	674 (LV)	± 3.8%	43%	46%	11%
Civiqs/Daily Kos	June 6–8, 2020	865 (RV)	± 3.8%	45%	48%	6%
Public Policy Polling (D) Archived November 13, 2020, at the Wayback Machine^{[upper-alpha 7]}	June 3–4, 2020	963 (V)	± 3.4%	43%	45%	12%
Public Policy Polling	April 30 – May 1, 2020	1,222 (V)	± 2.8%	43%	42%	14%
Public Policy Polling (D)^{[upper-alpha 6]}	December 13–15, 2019	944 (V)	± 3.4%	47%	41%	12%
Emerson College	October 13–16, 2019	888 (RV)	± 3.2%	47%	40%	14%
Lake Research Partners (D)^{[upper-alpha 8]}	April 24–29, 2019	500 (LV)	± 4.4%	56%	34%	–

Poll source	Date(s) administered	Sample size^{[lower-alpha 1]}	Margin of error	Joni Ernst (R)	Eddie Mauro (D)	Undecided
RABA Research/Eddie Mauro^{[upper-alpha 8]}	May 7–9, 2020	632 (LV)	± 3.9%	42%	42%	–
Lake Research Partners (D)^{[upper-alpha 8]}	April 24–29, 2019	500 (LV)	± 4.4%	58%^{[lower-alpha 12]}	33%	–
Lake Research Partners (D)^{[upper-alpha 8]}	April 24–29, 2019	500 (LV)	± 4.4%	49%^{[lower-alpha 40]}	44%	–

Poll source	Date(s) administered	Sample size^{[lower-alpha 1]}	Margin of error	Joni Ernst (R)	Generic Democrat	Undecided
Public Policy Polling	April 29–30, 2019	780 (V)	± 3.5%	48%	44%	–
Public Policy Polling (D)^{[upper-alpha 9]}	June 30 – July 1, 2017	784 (V)	± 3.6%	48%	41%	12%