His political resurrection and new status as front-runner has fueled talk of a watershed transformation within the Republican Party: a reconfiguration of the Reagan coalition.
That marriage of fiscal conservatives, the Christian right, and defense hawks has powered the GOP for the past 30 years, despite growing internal strains such as clashes between Western libertarians and Southern Evangelicals. But nothing has brought them more to the fore than the rise of the straight-talking, sometimes-brusque Republican senator from Arizona, whose place as presidential nominee was virtually assured Thursday after Mr. Romney's announcement.
"If I fight on in my campaign, all the way to the convention, I would forestall the launch of a national campaign and make it more likely that Senator Clinton or Obama would win," he says. "And in this time of war, I simply cannot let my campaign be a part of aiding a surrender to terror."
With that rather qualified endorsement from Romney, Senator McCain went on to address the annual meeting of conservative leaders with confidence and humility, analysts say. He insisted that he will govern with conservative principles – even acknowledging that he can't win without conservative support. But in true McCain fashion, he did not apologize for past stances that angered other conservatives.
"Many of you have disagreed strongly with some positions I have taken in recent years – I understand that. I might not agree with it, but I respect it for the principled position that it is," he told a cheering crowd that then became hushed. "It is my sincere hope that even if you believe that I have occasionally erred in my reasoning as a fellow conservative, you will still allow that I have ... maintained the record of a conservative."
Some conservative commentators, including Rush Limbaugh and Ann Coulter, have been adamantly opposed to mending fences with McCain. They see in him a liberal traitor who backs causes that are anathema to conservatives – such as embryonic stem-cell research and a path to citizenship for illegal immigrants. A McCain presidency, they argue, would tear apart the underpinnings of the house that Reagan built. Ms. Coulter has even advocated a protest vote for Democrat Hillary Rodham Clinton over McCain.
Yet other conservatives, like top Reagan administration officials Jack Kemp and Frank Donatelli, consider the rebel McCain to be a true heir to President Ronald Reagan's legacy because of his adherence to core principles despite political costs. These conservatives note that Reagan, too, was a maverick in his time – one who also was not afraid to take on the party establishment when he believed it had lost its bearings.
If Republicans are on the cusp of a major realignment, it would be a rare event in political party history, say political scientists. Some caution that it's not certain yet whether current rifts in the Republican base will yield the kinds of changes that transformed the Democratic Party when its New Deal coalition started to unravel during the 1960s.
"Once a coalition has been in place for some time, there begin to be tensions that fray various legs of the coalition," says Bert Rockman, a political scientist at Purdue University in West Lafayette, Ind. "Republicans are experiencing that now: The religious fundamentalists are clearly alienated from McCain, as are some of those in the no-tax group. [Republicans] may not completely fall apart, but they certainly may reconstitute themselves."
McCain also expressed confidence that he can "unite the party, bring us all together."
Some McCain supporters with strong conservative credentials, meanwhile, have lined up to persuade the disaffected that McCain is indeed a true conservative. In an open letter to "Our Conservative Colleagues," five former senior Reagan officials urged support for McCain as our "best and safest choice in 2008." In his time, Reagan also challenged the party establishment and created a new conservative coalition, they note.
"[S]ince the Reagan presidency, a new status quo, inconsistent with mainstream conservative principles and actions, has taken hold in the Republican Party, promoting practices, programs and principles inconsistent with the Party's character and traditions," the letter read. "Just as Ronald Reagan did in his time, John McCain now challenges this Establishment 'orthodoxy.' "
Mr. Donatelli, one of the letter's authors, says one thing that made Reagan a great president was that he knew what he wanted to do before he was elected. "McCain has a very clear sense of what he wants to do, and that is very, very important in a president," he says.
But for many Christian conservatives, McCain's record on their central issues is objectionable. They cite his support for embryonic stem-cell research and complain he has not come out strongly enough for repealing Roe v. Wade. Many fiscal conservatives, meanwhile, have not forgiven McCain for voting against the Bush tax cuts, although during his CPAC speech he again pledged to make them permanent. And then there's the Arizona senator's support for comprehensive immigration reform, for which he did apologize Thursday even as he insisted his first priority now will be to secure the borders.
"There are legitimate objections from some groups ... to what McCain has done on immigration," says Peter Wallison, a senior fellow at the American Enterprise Institute in Washington. "But this is a result of him being a straight talker who puts his reputation on the line for things he believes in, which is exactly what Reagan would do."
Many prominent conservatives are also urging McCain to clarify his stands on core conservative issues like abortion by pledging to appoint strict constructionist judges. They also want him to be clear that he will indeed fight for conservative causes.
"What he needs to do is, over a period of time, reestablish both credibility and relationships with conservatives," says David Keene, chairman of the American Conservative Union, which organizes the annual Conservative Political Action Conference. "Last year when he didn't come to CPAC he sort of dismissed the whole thing, saying, 'I don't have to talk to these conservative leaders, because conservatives around the country are for me.' Well, that's not true, and you've seen that – I mean, even in his home state, he did not carry self-identified conservatives in the [Tuesday] primary."
McCain made clear that he knows he must bring the far right into the voting booth to win the White House. That's an assessment with which many analysts agree.
"It's a given [that] he has to have a lot of conservative votes to win," says Alfred Regnery, author of "Upstream: The Ascendance of American Conservatism."
The apparent success of his CPAC speech notwithstanding, that will still be a challenge. Mr. Limbaugh has said he'd rather sit out this election than see McCain in the White House. That kind of allegiance to conservative ideology over party loyalty could cause McCain problems. "McCain has to be worried about that.... If he doesn't have a united party, he'll sink," says Larry Sabato, a political analyst at the University of Virginia in Charlottesville.
Many analysts also suggest that Limbaugh and others on the far right will have little impact once the general election comes around.
"Once McCain becomes the nominee, the establishment will have to take him and then they'll start seeing a beauty in him that they hadn't before," says Stephen Hess, a senior fellow at the Brookings Institution. "Why? Because their fate is suddenly locked in with his."
Even if McCain can consolidate the base during this election, the fractures that have been exposed in the Republican Party will remain, says some analysts.
"John McCain is kind of a transitional figure," says Michael Tanner of the Cato Institute, a libertarian think tank in Washington. "He'll be a place holder while the Republican Party figures out what it wants to be."
• Staff writer Linda Feldmann in Washington contributed to this report.