The Idaho Democratic Party is the affiliate of the Democratic Party in the U.S. state of Idaho.

While the party has been in the minority for most of the state's history, it has produced several notable public figures, including former U.S. senator Frank Church and former governor and secretary of the interior Cecil Andrus. Trade union support has traditionally been a key component of Democratic success in Idaho.^[2]

Created in 1863 after the discovery of new mining territory, the early Idaho Territory was heavily populated by settlers from western Oregon, California and Nevada who supported a radical Republican agenda. However, towards the end of the war, Idaho became flooded with Confederate refugees from states like Missouri who voted, like the miners in Idaho, heavily Democratic. The state became a Democratic stronghold for the next two decades.^[3]

At the dawn of statehood, despite ceding Idaho almost entirely four years earlier to the Populists and Republicans (Cleveland won only 2 popular votes in 1892), a fusion Populist/Democratic ticket behind William Jennings Bryan's candidacy won the state with 78.1% of the vote with the support from Silver Republicans. Nevertheless, the three– man congressional delegation remained two-part Populist, one-part Republican.

It was not until the turn of the century that Idaho saw its first Democratic representation in Congress, Senator Fred Dubois, U.S. Marshal of the Idaho Territory and a former Republican. He successfully campaigned on the disenfranchisement of Mormons on the grounds that they broke the law by practicing polygamy, already having barred them form holding office while he held office in the state legislature. Ironically, while his anti– Mormonism as a Republican kept Democrats out of office after 1882, his anti-Mormonism as a Democrat had the same result after 1902.^[3]

Though Democrats and Jewish governor Moses Alexander were able to implement a radically progressive agenda with the backing of the Nonpartisan League while in control during Woodrow Wilson's presidency, they quickly ceded power and it was not until Franklin Delano Roosevelt's 1932 landslide that they began to turn out state and local (as well as national) Republican office holders for a sustained period of time.^[3] That year, all three congressional Republicans up for re– election were defeated by Democratic challengers by at least 11 percent. All three challengers, like their state party, were stalwart supporters of FDR's New Deal. Despite a turn of opinion against the federal government's programs years later, Democrats retained two of their three newly attained seats for at least 15 years and managed to control the legislature for eight until the chambers evened themselves out during and immediately after the war.^[3]

• Lauren Necochea
• Deborah Silver
• Fred Cornworth^[6]
• Evangeline "Van" Beechler^[7]
• Bert Marley^[8]
• Larry Kenck^[9]
• R. Keith Roark^[10]
• Larry Grant^[11][12][13]
• Richard H. Stallings^[14][15]
• Carolyn Boyce^[16]
• Kathie Garrett^[17]
• Bill Mauk^[18][19][20]
• Mel Morgan^[21][22]
• A. K. Lienhart– Minnick^[23][24]
• Conley Ward, 1988–1991^[25]
• George Klein 1978^[26][27]
• John F. Greenfield 1976–77^{[28][29][30][26][31][32][33]}
• A. W. "Bill" Brunt 1952–1954^[34]
• John G. Walters 1958
• John Glasby
• George A. Greenfield 1954– 1955^[26]
• Gilbert Larsen ?–1952
• Ed P. Brennan 1949
• Dan J. Cavanagh 1947–1948
• David L. Bush 1944–1946
• Ben W. Davis 1939
• Ira H. Taylor 1937
• T. A. Walters 1931
• Edwin M. Holden 1930
• L. E. Dillingham 1925–1929
• Dr. W. R. Hamilton ?–1918
• Joseph T. Pence 1914
• Ben R. Gray 1912
• John F. Nugent^[35]
• Kirtland I. Perky 1900–1902
• George Ainslie 1890–1891
• Wayne P. Fuller 1979–1980

• Political party strength in Idaho
• Idaho Democratic caucuses, 2016
• Idaho Democratic caucuses, 2012
• Idaho Democratic caucuses, 2008