Arlen Specter, formerly a member of the Democratic Party, had served as legal counsel to the Warren Commission, which investigated the 1963 assassination of President John F. Kennedy, after which he became District Attorney of Philadelphia.

During the Republican primary, Specter faced state senator Edward Howard, as well as Delaware County councilman Bud Haabestad, who was endorsed by Schweiker, then-governor Thornburgh and John Heinz.

Specter distanced himself from Governor Dick Thornburgh, who had become unpopular due to his proposals to decrease welfare program spending.

[1] In the end, Specter defeated Flaherty by approximately 108,000 votes, carrying Philadelphia and its suburbs as well as the central and northeastern portions of the state.

Flaherty performed strongest in the western portion of the state, including Cambria, Clarion, Erie and Mercer counties.