Pennsylvania's 10th congressional district is 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 due to gerrymandering. They added State College to the old district's boundaries while removing some Democratic-leaning areas and redesignated it the twelfth district, and they reassigned the tenth district to an area around Harrisburg and York. The new tenth district is represented by RepublicanScott Perry, who previously represented the old fourth district. 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, DemocratChris Carney unseated Sherwood by a 53%–47% margin. 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, Pennsylvania, 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.
District boundaries 2003–2013
The Pennsylvania 10th was the third-largest congressional district in the state. The district encompassed the following counties and areas:
Rep. Tom Marino declared his intent to run for his 4th term and was uncontested in the Republican Primary. Originally, no Democratic candidates filed to run for office, upon this revelation, Mike Molesevich, an environmental contractor and former LewisburgMayor, announced he would seek a write in campaign to get on the general election ballot. Write-in candidates need over 1,000 votes in the Primary election to appear on the ballot in the 2016 general election. Mike Molesevich succeeded in his effort, receiving 2425 votes, earning a spot on the general election ballot. Jerry Kairnes of Lycoming County announced that he would seek to be on the November ballot as an Independent, but dropped out after Molesevich earned a spot on the ballot
