Pennsylvania ratified the United States Constitution on December 12, 1787, and elects its U.S. senators to class 1 and class 3. Officeholders are popularly elected, for a six-year term, beginning January 3. Elections are held the first Tuesday after November 1. Before 1914, they were chosen by the Pennsylvania General Assembly; before 1935, their terms began March 4. The state's current U.S. senators are Democrats Bob Casey Jr. (since 2007) and John Fetterman (since 2023). Arlen Specter was Pennsylvania's longest-serving senator (1981–2011).

List of senators

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