Depending on whom you talk to, Rendell's omnipresence on the campaign trail, enormous popularity, and fine-tuned political machine are responsible for between two and five points of Clinton's nearly double-digit win.

"Clinton has gotten support from other governors in other states, but she has been served better and stronger [by Rendell] than anyone else," said Clay Richards, assistant director of the Quinnipiac University Polling Institute, who attributed two to three points to the Rendell factor.

For contrast, some point to the other top Democrat in the state, Sen. Bob Casey, who endorsed Sen. Barack Obama but was unable to deliver critical votes from heavily Catholic areas in the west or even in his own hometown of Scranton - where the Casey family has reigned as political royalty for a century and a half.

"I thought his endorsement of Barack Obama would stop the bleeding in the northeast," said James Hoefler, a political science professor at Dickinson College in Carlisle. "But, apparently, it didn't."

Clinton won by a 3-1 ratio in Casey's home county of Luzerne.

Casey agreed Rendell was "a great asset" to Clinton, but said in an interview that she also benefited from her husband's two presidential campaigns in the state, as Casey did from the campaigns of his father, Gov. Robert P. Casey.

Speaking to reporters in a conference call, Rendell dismissed any role he might have played in Clinton's win, and argued Casey should not be blamed for Obama's defeat.

"I think endorsements by politicians for president don't mean jack," Rendell said yesterday. "That was clearly proved with the Bob Casey endorsement. . . . Casey voters around the state voted for Clinton, 70-30, and in his hometown [Scranton], 75-25."

Rendell added: "The city I come from" - Philadelphia - "voted for Sen. Obama, 65-35. I didn't do such a hot job."

T.J. Rooney, the state Democratic Party chairman, said he believed Rendell might have been worth five points to Clinton.

"It was about a politician not just endorsing a candidate but then going to the nth degree," said Rooney. "Rendell expended a lot of political capital, and that's what separates him from others."

Rendell said that he might have helped generate enthusiasm for her campaign, recruited Pennsylvania mayors to back her, and given advice on where to go in the state, but that Clinton herself was responsible for the full margin of victory. Although, he added, "maybe one point to Chelsea."

Richards recalled a question on one of his polls a few weeks ago asking whether Rendell made a difference in voters' decisions, and he said the responses were split about evenly.

But Richards said it would be impossible to ignore Rendell's get-out-the-vote influence and guiding hand through the state as important factors. Together, Rendell and former President Bill Clinton - who made dozens of appearances across Pennsylvania for his wife - make a formidable team, he said.

Rendell is "the second-best politician in the country," said Richards, "and she's married to the best."

The Clinton campaign hopes the Rendell magic will rub off outside Pennsylvania. Rendell said the campaign asked him to help in the coming primaries and he agreed.

But Rendell, who had been attacked by some Republican state lawmakers for shirking his gubernatorial duties over the last six weeks - a charge he denied - added that he was available only on weekends.

To Casey, Obama's defeat had a silver lining: The Illinois senator cut Clinton's 20-point lead in half, establishing a foundation of support that could serve him well in the general election.