 
A special election was held on May 21, 2019, to fill the remainder of the term for Pennsylvania congressional district in the United States House of Representatives for the 116th United States Congress. Tom Marino, a Republican, resigned from office effective January 23.
Background.
As a result of the 2018 elections, Pennsylvania's House delegation to the 116th U.S. Congress took office in early January 2019 with a tie of 9 Republicans and 9 Democrats.
Republican Tom Marino, the incumbent representative for Pennsylvania congressional district, announced his resignation effective January 23, 2019. By state law, Governor Tom Wolf was required to call for a special election at least 60 days after the seat became vacant. Wolf set the election for May 21. Primary elections were not held in the race. Instead, nominees were chosen by each party. Republicans selected their nominee on March 2.
Democratic selection.
According to the Pennsylvania Democratic Party, Marc Friedenberg, the Democratic nominee for the district in 2018, was the only individual who submitted an application to be the nominee. Therefore, the convention was cancelled, and the party declared Friedenberg the nominee on February 12.
General election.
Endorsements.
 ;templatestyles src="Endorsements box/styles.css"/ ;Fred Keller (R)
Federal politicians
Local officeholders
Organizations
 ;templatestyles src="Endorsements box/styles.css"/ ;Marc Friedenberg (D)
Federal politicians
Statewide and local politicians
Labor unions
Organizations
Results.
! scope="col" colspan="2" style="width: 130px"|Party
! scope="col" style="width: 17em"|Candidate
! scope="col" style="width: 5em"|Votes
! scope="col" style="width: 3.5em"|%
! scope="col" style="width: 3.5em"| ;templatestyles src="Template:Tooltip/styles.css" / ;±%
! colspan="3" style="text-align:right;" | Total votes
References.
 ;templatestyles src="Reflist/styles.css" / ;
External links.
Official campaign websites