Sen. Arlen Specter, in leaving the party that gave birth to his political rise and supported his career in the Senate for five terms, fired a parting shot at the GOP on Tuesday that infuriated Republicans.

"As the Republican Party has moved farther and farther to the right, I have found myself increasingly at odds with the Republican philosophy and more in line with the philosophy of the Democratic Party," he said at a news conference.

But Republican National Committee Chairman Michael Steele noted that Specter had no problem seeking help from conservatives Rick Santorum and George W. Bush in his last re-election bid.

"Is this the same Republican Party, the same rightward-tilting Republican Party that saved his hide in 2004?" Steele said. "To whom he went running and pleading for support because he couldn't make it through a Republican primary?"

Other voices on the right also objected to Specter's characterization of the party.

"I don't think there's evidence that the Republican Party has shifted heavily to the right," said GOP analyst Michael Barone.

GOP pollster Whit Ayers said, "It's hard to identify a lot of issues on which the GOP of today is actually more conservative than it was in 2000, 2002 or 2004, when it won national elections."

And while economic issues dominate today's political debates, some Republicans don't even see a rightward shift on social issues.

"I don't really see any evidence that Republicans are for example coming forward and emphasizing conservative positions on cultural issues," Barone said.

Ayres has launched a Web site, www.resurgentrepublic.com, in an effort to revive the GOP. And he argues its current problems are the result not of an ideological shift but a response to controversies.

"In 2006, independents voted for Democrats rather than Republicans largely out of frustration with Iraq," Ayres said.

And some note that John McCain, the Republican presidential nominee last year, was hardly a die-hard conservative ideologue.

Ayres says the country as a whole is center-right and that the GOP actually has the support of a broad segment of voters.

"The public would rather have smaller government and lower taxes than larger government and higher taxes," Ayres said. "The public is also center-right on national security issues."

His polls even show a majority of Americans think Guantanamo Bay helped make America safer, while many Democrats argue it undermined our values. So the center of gravity in the GOP, he argues, is much closer to the majority of the country than Democratic party ideas are.