Note: This column has been revised since its original posting.

WASHINGTON — The great drama in American politics today revolves around the question: What is the Republican Party?

We think we know. Republicans are the party of business and of evangelical Christians, of better-off voters and people who hate taxes, the party of conservatism and the South, the party that wants to be aggressive in the war on terror.

But the instability in the Republican presidential campaign, the longing for a Fred Thompson candidacy, and the sharp split over immigration all point to an identity crisis at the end of the Bush era.

The last great redefinition of Republicanism, kicked off in 1964 with Barry Goldwater’s nomination, was resolved with Ronald Reagan’s election in 1980. Republicans bled liberals and embraced conservatism.

President Bush’s goal to turn this alignment into a long-term majority was, at first, advanced by the public’s reaction to the attacks of Sept. 11, 2001. Bush’s trump card, like Reagan’s, was the assertion that Republicans were smarter and tougher on foreign policy than Democrats.

But the failure in Iraq has turned the party’s trump card into a joker at the very moment when the war has become the defining characteristic of the Bush presidency.

Largely forgotten are compassionate conservatism, Bush’s early emphasis on education reform, even his close identification with Americans who are both conservative and religious.

The most surprising finding of a Pew Research Center poll released earlier this month is that only 44 percent of white Evangelical Protestants approved of Bush’s handling of his job, down from a peak of 95 percent in October 2001.

Rudy Giuliani has managed to stay on top in the Republican polls, despite his relative social liberalism, largely because Bush has imprinted national security as the Republicans’ defining issue. Giuliani’s entire campaign has rested on the tough image he cultivated in the weeks after 9/11.

But since the beginning of the year, Giuliani’s support has dropped from the 35 percent to 40 percent range to about 25 percent among Republican voters. There is good reason to believe he will slip further. The Pew survey, for example, found that only 43 percent of Republicans identified him as the party’s pro-choice candidate. As awareness of his position among anti-abortion Republicans goes up, his support could go down. More importantly, the exhaustion with Bush, and Bush’s close association with the war on terrorism, could make national security less of a voting issue as the year goes on. If the security constituency shrinks, so will support for Giuliani.

Thompson has emerged as the back-to-the-future candidate on whom many Republicans seem ready to project all their aspirations. His supporters are the core of the old Goldwater-Reagan fan club. The Pew survey suggested that voters well disposed toward Thompson are more likely to attend church than Giuliani sympathizers, be somewhat more conservative, older, better educated and overwhelmingly male. A recent Washington Post/ABC News survey indicated that Thompson is especially strong in the South.

This makes Thompson a particular threat to Mitt Romney, who has used heavy spending to push himself to the top in the Iowa and New Hampshire polls and had hoped to be the sole candidate of the conservative restoration. The flow of the contest has left John McCain in the worst of all possible positions: He is closely identified with Bush in support of an unpopular war and of an immigration bill despised by the party’s base.

All this has won McCain well-deserved courage points in his old press constituency, but few new enthusiasts among Republicans. No wonder McCain’s campaign this week, looking for an opening somewhere, went after Romney’s flip-flopping on abortion.

With the new Wall Street Journal/NBC News poll showing Americans giving the Republican Party “their most negative assessment” in the survey’s two-decade history, the party’s presidential contest has become a battle of unhappy warriors.

This disaffection explains the pure rage in many parts of the party over immigration. By highlighting the failure of border enforcement, the battle has given rank-and-file Republicans an acceptable channel for venting against the administration’s incompetence. It has also become the focus of Republican doubts about Bush-style internationalism and, especially for less affluent Republicans, a means for expressing legitimate economic and cultural anxieties.

This could be the new Republican Party in the making: a disappointed, dissatisfied and inward-looking coalition that abandons Reagan’s hopefulness and tries to hang on by playing on fears of terrorism and anger about immigration. If Fred Thompson’s job is to restore optimism to a dispirited bunch, he faces a task that might have overwhelmed even Ronald Reagan.

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

© 2007, Washington Post Writers Group

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