Pennsylvania's 10th congressional district is currently located in the south-central region of the state. It encompasses all of Dauphin County as well as parts of Cumberland County and York County. The district includes the cities of Harrisburg and York. Prior to 2019, the district was located in the northeastern part of the state. The Supreme Court of Pennsylvania redrew the district in 2018 after ruling the previous map unconstitutional because of gerrymandering. The court added State College to the old district's boundaries while removing some Democratic-leaning areas and redesignated it the twelfth district; an area encompassing Harrisburg and York was numbered as the "10th". The new tenth district is represented by Republican Scott Perry, who previously represented the old fourth district.^[3]

The district was one of the 12 original districts created prior to the 4th Congress. In 2006, when it was still located in northeastern Pennsylvania, the 10th district experienced one of the greatest party shifts among all House seats that switched party control: in 2004, Republican Don Sherwood won with an 86% margin of victory over his nearest opponent and two years later, Democrat Chris Carney unseated Sherwood by a 53%–47% margin.^[4] In 2008, Carney won reelection by 12 points but the district swung back in 2010, electing Republican Tom Marino. The district was mostly Republican in its political composition, an aspect of the district that was reflected especially well in presidential elections. In 2004, President George W. Bush won 60 percent of the vote in the district and in 2008, Senator John McCain beat Senator Barack Obama here by a margin of 54 percent to 45 percent. Nonetheless, Carney easily won reelection as a Democrat the same year McCain won the district. However, in the 2010 midterm elections, Marino unseated Carney by a 55%–45% margin. In 2016, local businessman and former mayor of Lewisburg, Mike Molesevich challenged Marino for the seat, but he fell to the Republican in November by more than two to one. In 2018, Marino won election to a redrawn 12th district; while he remained the congressman for the 10th district into January 2019, he moved within the new district's boundaries beforehand.

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According to the APM Research Lab's Voter Profile Tools^[6] (featuring the U.S. Census Bureau's 2019 American Community Survey), the district contained about 559,000 potential voters (citizens, age 18+). Of these, 80% are White, 10% Black, and 6% Latino. Immigrants make up 5% of the district's potential voters. Median income among households (with one or more potential voter) in the district is about $67,300, while 9% of households live below the poverty line. As for the educational attainment of potential voters in the district, 9% of those 25 and older have not earned a high school diploma, while 30% hold a bachelor's or higher degree.

District created in 1795.

• 2003–2013
• 2013–2019
• 2019–2023

• List of United States congressional districts
• Pennsylvania's congressional districts

• Martis, Kenneth C. (1989). The Historical Atlas of Political Parties in the United States Congress. New York: Macmillan Publishing Company.
• Martis, Kenneth C. (1982). The Historical Atlas of United States Congressional Districts. New York: Macmillan Publishing Company.
• Congressional Biographical Directory of the United States 1774–present