In interviews, Clinton supporters said they saw in Obama a presumption that had made it hard to give him their allegiance. Some said they were put off by his decision to accept the Democratic nomination at a football stadium that can hold more than 76,000; his use of a knockoff of the presidential seal at a campaign event; and his early interest in giving his Berlin speech at the famous Brandenburg Gate, where Reagan spoke in 1987.
The Republican National Committee has been pumping out regular e-mails titled "Audacity Watch," a compilation of instances in which, in its view, Obama has appeared to act as if he were president. In an e-mail sent Thursday, the RNC mentioned a news report that he had already instructed aides to begin planning for a transition to the presidency.
Amy Siskind of Westchester, N.Y., is a Clinton supporter who said she wouldn't vote for Obama. Siskind said she was especially offended when Obama hired Clinton's former campaign manager, Patti Solis Doyle, to work with his vice presidential nominee. Given that Solis Doyle was demoted by Clinton, the appointment was perceived by Clinton loyalists as a slight.
"Most folks feel that the battle is over and he's the winner, but he's really acted like a sore winner," Siskind said. "If Hillary had been the nominee, you would have seen a much more deferential approach to Obama supporters."
Lynn Forester de Rothschild, a Clinton fundraiser who lives in New York City, said, "What I think is very important is that he has a problem with his image. He is an aloof candidate. He does not connect with people. He has words, but no ordinary person thinks that he is there for them, and women feel that intensely."
Time remains for Obama to unify the party and find ways to win over skeptical voters. His campaign released ads last month that emphasize the parts of Obama's life story that a typical voter might find appealing. Obama, for example, was raised by a single mother and grandparents who lacked substantial means.
The campaign hopes that the images in those ads will boost his standing in the polls.
"As we tell Sen. Obama's story -- being raised by a single mother, pulling himself up, working his way through school -- people will become more familiar with him," said Hari Sevugan, an Obama campaign spokesman.
Seeing an opportunity, McCain's supporters have sought to drive home perceptions that Obama doesn't connect with average voters.
"The fact that Obama is out of touch with voters . . . is certainly something we'll continue to reiterate," said Alex Conant, a spokesman for the Republican National Committee. "To the extent that he's acting as if he's already president when the election is over 100 days away and everyone expects it will be a very close race raises questions about how in touch he is."
Times staff writer Maeve Reston in Columbus, Ohio, contributed to this report.