Margolies lost Tuesday in the 13th Congressional District, which includes areas in Northeast Philadelphia and suburbs. State Rep. Brendan Boyle was the clear winner less than two hours after polls closed.
Bill Clinton endorsed Margolies, who was elected to Congress in 1992 -- the year he was elected president -- only to lose her seat in the Republican congressional landslide of 1994. She cast the deciding vote for Clinton's 1993 budget -- which did not help her chances of re-election.
Margolies, 71, lives in Plymouth Township and heads Women's Campaign International in Philadelphia. She is also an adjunct professor at the University of Pennsylvania.
While Margolies ran well in suburban Montgomery County, Boyle won about three-quarters of the vote in Philadelphia. He was the only one of four Democratic candidates who lives in the city.
The seat was open because Rep. Allyson Schwartz, D-Pa., decided to run in the Democratic gubernatorial primary, losing to York businessman Tom Wolf.