Edgar's preparation for staff leadership of the NCC was widely varied and included United Methodist pastorates, a college chaplaincy and community activism in the form of Philadelphia's People's Emergency Center, which he helped launch in 1972.

In 1974, dismayed by Watergate – especially the "Saturday Night Massacre: on October 20, 1973, When President Nixon fired his attorney general and deputy attorney general when they refused to fire the Watergate Special Prosecutor – Edgar decided to run for Congress in 1974.

Bob Edgar became the first Democrat in 120 years to be elected from the heavily Republican Seventh District of Pennsylvania.

He maintained his friendship with both Democrats and Republicans, as evidenced by his friendship with U.S. Senator Dick Schweiker, a Republican and Ronald Reagan's 1976 choice for vice president.