The Republicans' identity crisis is producing the most volatile presidential primary season in memory and threatening to dilute the conservative fervor that swept the party to huge wins in 2010.
Former Massachusetts Gov. Mitt Romney is the pragmatic, establishment choice. But he has yet to attract more than a quarter of GOP voters, as his eight-vote Iowa caucus win showed.
So long as huge numbers of restless, overwhelmingly conservative Republicans keep yearning for an alternative, the party risks losing the fiery intensity that gave it the House majority and brought much of President Barack Obama's agenda to a standstill.
Romney promises to use his corporate skills to do a good job managing the government. But many party activists seem more intent on radically reshaping that government, sharply diminishing its role in Americans' lives. That sentiment gave birth to the tea party in 2009, dominated the 2010 elections and now seeks a champion in the 2012 presidential contest.
Former Sen. Rick Santorum, perhaps best known for his crusades against abortion and gay marriage, is the latest contender to emerge as the non-Romney alternative. He came from far back to finish within an eyelash of an Iowa victory. But he will be hard-pressed to raise the money and build the ground game needed to compete in New Hampshire, South Carolina, Florida and beyond.
Former House Speaker Newt Gingrich and Texas Gov. Rick Perry are in weaker shape, having finished fourth and fifth in Iowa, respectively. Yet a survey of Iowa caucus-goers shows there's an untethered mass of conservative voters still ripe for the picking.
Establishment Republicans predict those voters will eventually make peace with Romney because of their antipathy to Obama. That's not the most inspiring way to win a presidential nomination, as an angry Gingrich noted Wednesday.
Gingrich, who was hammered by attack ads from Romney's allies in Iowa, told MSNBC, "What is really striking about last night is that three out of four Republicans repudiated Mitt Romney. How can you take seriously somebody after that kind of campaign?"
The Iowa results have prodded at least one prominent conservative leader to schedule a series of meetings and urge like-minded groups to embrace Santorum.
"It's time for the conservatives to get off the sidelines and get into the arena," said Richard Viguerie. "Conservatives have dug in their heels, and they just don't want Romney."
A survey of Iowans entering Tuesday's GOP caucuses drove home the point that Romney is the choice of comparatively pragmatic Republicans whose top goal is ousting Obama. About a quarter of his supporters called themselves "very conservative," compared to two-thirds of Santorum's supporters.
More than three in five Romney backers were chiefly looking for a candidate who could beat Obama. That's four times the number of Santorum supporters who gave that answer. Meanwhile, two in five Santorum supporters, and virtually none of Romney's, said they were looking for a "true conservative."
The survey of caucus-goers, conducted by a news consortium including The Associated Press, suggests there's less difference between the tea party and the Republican Party than many may have thought.
Self-identified tea party supporters made up 64 percent of GOP Iowa caucus-goers. Santorum was backed by 29 percent of them, while Romney and libertarian-leaning Rep. Ron Paul of Texas took 19 percent each. Gingrich got 15 percent and Perry 11 percent.
Romney's tepid support from tea partyers and other strong conservatives means that, at best, he will have to labor to win the nomination and then would enter the general election with a restless base.
Romney did well in Iowa, "but in Santorum, the right now has what it's been looking for: a conservative who is viable in a fight for the nomination," said GOP consultant Terry Holt. "Those Paul, Gingrich and Perry supporters have to go somewhere eventually," Holt said, "and it still doesn't look like any of them are ready to embrace Romney."
The further right Romney has to move to win their backing, the harder it will be for him to woo independent voters next fall.
It's unclear whether the tea party can match the influence it has wielded in congressional elections.
Romney's even-tempered style clashes with the House GOP firebrands who see compromise as a weakness. They pushed the government to the brink of default in last summer's showdown over the debt ceiling. And they have caused massive headaches for Speaker John Boehner, R-Ohio, on a payroll tax cut and other issues.
It's hardly the first time Republicans have struggled for their identity. A clash between Northeast moderates and Sunbelt conservatives led to Barry Goldwater's nomination for president in 1964. He lost in a landslide to Lyndon Johnson.
But Goldwater redefined the GOP as a solidly conservative force ready to stop the march of New Deal and Great Society liberalism. He paved the way for Ronald Reagan and more sharply defined philosophies in both parties.
"It's not new," said Mickey Edwards, a former House Republican from Oklahoma. He predicted that most Republican voters eventually will gravitate to Romney, as the desire to oust Obama will trump the desire for a more ideological party leader.
"Now they're looking for who's not Mitt," Edwards said. "Next they'll look for who's not Obama."
Such thinking might yield a party identity that disappoints staunch conservatives who want a new era of dramatically stripped-down government spending, taxation and regulation. For them to prevail, however, they'll have to find a way to unite anti-Romney sentiment behind one candidate who can go the distance.
Associated Press writers Laurie Kellman, Alan Fram and Deputy Director of Polling Jennifer Agiesta contributed to this report.