Democratic elected officials joined staffers and volunteers as the Barack Obama campaign reopened its Philadelphia office with a party on Thursday evening. The event marked one of the strongest, though not the first, endorsement of Obama's candidacy by Philadelphia mayor Michael Nutter, who had been a high-profile Hillary Clinton supporter until she left the race on June 7th.

The campaign's local headquarters, housed in an airy fourth-floor room, were crowded but not crammed on a typically humid summer night, and attendees set upon cheesesteaks and lawn signs with equal vigor. City Council members Curtis Jones Jr and Bill Green Jr spoke first, outlining the campaign's goal of gaining a high Philadelphia turnout and an overwhelming majority in the city in order to eke out an overall statewide victory in Pennsylvania.

Nutter, the evening's biggest draw, palpably boosted the energy level in the room when he entered and made his way to the microphone, dispensing measured handshakes and crinkly-eyed smiles. The mayor's technocratic style and hard-fought victory in 2007's five-way mayoral race would have made him a natural Obama ally -- had the Illinois senator not endorsed Nutter's chief rival, establishment candidate and congressman Chaka Fattah, during the mayoral primary.

Upon winning the mayor's office, Nutter joined Pennsylvania Governor Ed Rendell in campaigning hard for Clinton in the closely contested Pennsylvania presidential primary, which the New York senator won with a nine-point margin. After Clinton left the race, Nutter appeared with Rendell and Obama at a June 13th fundraiser and presented a unified front in support of the presumptive nominee. At last night's event, he was unequivocal, saying that he was being "a good Democrat" in backing Obama, and calling the campaign "our new civil rights moment."