WASHINGTON — If John McCain secures the Republican presidential nomination, his victory would signal a revolution in American politics — a divorce, after a 28-year marriage, between the Republican and conservative establishments.

McCain would be the first Republican nominee since Gerald Ford in 1976 to win despite opposition from organized conservatism, and also the first whose base in Republican primaries rested on the party’s center and its dwindling left. McCain is winning despite conservatives, not because of them.

Those who built the American right, from Barry Goldwater in 1964 through the Reagan and Gingrich revolutions, are intensely aware of the dangers a McCain victory portends. Some on the right feel it would be less damaging to their cause to lose the 2008 election with the Republican-conservative alliance intact than to win with John McCain.

For those outside the conservative movement, such anxiety seems strange. McCain’s voting record in the House and Senate has typically won high ratings from conservative groups. His positions on key issues (support for the Iraq war, opposition to abortion, his long-standing criticism of government spending) are those of an orthodox, conservative loyalist.

If McCain is the nominee, Democrats will have plenty of ammunition to persuade middle-of-the-road voters that he is not a moderate. And in Wednesday’s California debate, McCain repeated his oft-declared claim that he had been a “foot soldier” in Ronald Reagan’s army.

But staunch conservatives see things differently. They know that in primary after primary, McCain’s base has been formed by moderates, liberals, independents, supporters of abortion rights and critics of President Bush. Conservatives — who mistrust McCain because of his history on taxes, immigration, global warming and campaign finance reform — were not his coalition’s driving force. And Republicans who describe themselves as “very conservative” have consistently rejected McCain. In this week’s Florida primary, such voters backed Mitt Romney over McCain by more than 2 to 1.

Vin Weber, a former member of Congress who backed McCain in 2000 but supports Romney this year, said the confusion outside Republican ranks is not surprising. “People usually think that the conservative leadership and the Republican leadership are one and the same, but they’re not,” Weber said.

McCain has gotten to where he is because conservatives failed to agree on a single standard-bearer. Mike Huckabee has consistently peeled off religious conservatives. Fred Thompson further splintered the conservative vote, particularly in South Carolina. Both foiled Romney’s hope of becoming the early alternative to McCain. Moreover, because Romney changed his stand on a number of issues important to the Republican right, many in the rank and file never fully trusted him.

Rudy Giuliani’s decision to make his stand in Florida left moderate votes to McCain in the earlier primaries. This allowed McCain to consolidate his position.

Significantly, many of the leading Republicans championing McCain have never been heroes to the right. Giuliani, a social moderate, quickly endorsed McCain after dropping out on Wednesday. Gov. Charlie Crist, who helped McCain in Florida, earned his popularity as a moderate and appeals to independents and even Democrats. Gov. Arnold Schwarzenegger, who backed McCain on Thursday, has veered far from conservatism and now works closely with Democrats in the California Legislature.

All this explains the ferocity of the continued resistance to McCain among conservative leaders. Rush Limbaugh has served as a spokesman for their cause. On his radio show Wednesday, Limbaugh excoriated those who “pretend that Sen. McCain is the choice of conservatives when exit poll data from every primary state show just the opposite.”

“He is not the choice of conservatives, as opposed to the choice of the Republican establishment — and that distinction is key,” Limbaugh declared. “The Republican establishment, which has long sought to rid the party of conservative influence since Reagan, is feeling a victory today as well as our friends in the media.”

McCain, of course, has yet to secure the nomination, and his performance in Wednesday’s debate was less than inspiring. His straight talk took a crooked path when he repeatedly refused to say whether he would now vote for his own immigration bill. McCain’s self-satisfied smile as Romney tried to defend himself against his opponent’s essentially false characterization of the former Massachusetts governor’s position on the Iraq war was hardly the visage of a gracious winner.

But as one prominent conservative noted Wednesday night, Republican elected officials are starting to fall into line behind McCain, despite their reservations, simply because they think he will win. Their capitulation signals the end of the Reagan-Bush era and the beginning of something quite different.

E.J. Dionne’s e-mail address is postchat(at)aol.com.

© 2008, Washington Post Writers Group

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