HARRISBURG, Pa. (AP) — It looked like progressive Chris Rabb had a mountain to climb to win the Democratic nomination for a congressional district in Philadelphia.

The mayor and the city’s Democratic Party had endorsed another candidate in this week’s primary. So had members of Pennsylvania’s delegation in the U.S. House. One Rabb rival was backed by millions of dollars. A second benefited from a get-out-the-vote operation run by the influential local building trades unions.