Obama, introduced by Vice President Biden, spoke for 28 minutes, arguing that it would be wrong to go back to the Republican economic policies that "left such a big mess." He said the GOP should not be rewarded for what he called its cynical obstructionism aimed at a short-term electoral victory.
City officials estimated 18,500 people turned out for the late-afternoon event in a field next to Robert Fulton Elementary School, though it was hard to see how so many could fit in the space. Organizers said there were several overflow lots where people listened on speakers. They were all treated to the hip-hop band the Roots, DJ Diamond Cut, and some red-meat political remarks.
In Pennsylvania, the Democratic ticket faces an uphill run in state races. Polls show Senate candidate Rep. Joe Sestak trailing his Republican opponent, Pat Toomey, and Democratic gubernatorial nominee Dan Onorato down by double digits to his GOP rival, Tom Corbett, the state attorney general.
To have any prayer of winning those races, the Democrats must pump up the vote in Philadelphia and Pittsburgh, as Obama did two years ago in carrying the state by 10 percentage points over Republican Sen. John McCain.
Nationally, polls have shown that Republican-leaning voters, energized in part by the tea-party movement, are more intensely interested in the election and considered more likely to vote.
A president's party almost always loses congressional seats in midterm elections. But this year, Democrats, burdened by high unemployment and voter angst, are trying to avoid heavier-than-usual losses in the midterms.
