DOYLESTOWN, Pa.—Rep. Patrick Murphy, a fresh-faced rising Democratic star and loyal backer of President Barack Obama’s agenda, is facing the fight of his life in a suburban Philadelphia district Mr. Obama won easily two years ago.
Across Pennsylvania, another Democrat, Rep. Jason Altmire, is competing in a district Republican John McCain took by a wide margin. Mr. Altmire is running away with it, by running away from the president.
In their contrasting fates lie broader lessons for the coming midterms: Live by the president and you could die by the president. Democrats who have been thorns in the president’s side are doing well in some of the toughest districts for their party, from Alabama to the steel belt of western Pennsylvania. But swing-district Democrats who have voted with the president in Congress are struggling, even if they’re now asserting their independence.