DES MOINES, Iowa - Former Arkansas governor Mike Huckabee rode a wave of evangelical fervor to victory over Mitt Romney in Iowa's Republican caucuses Thursday, a win in the first presidential voting that is stunning because it hardly seemed possible two months ago.

In an interview with Fox News, Romney compared the race to the first inning of a 50-inning baseball game. “I'm going to keep on battling all the way, and anticipate I get the nomination when it's all said and done,” he said. “But you know, congratulations for the first round to Mike, and we'll go on to New Hampshire.”

After spending nine months near the bottom of the pack, Huckabee surged to become the front-runner in Iowa in December and never relinquished the position, despite a barrage of negative ads from Romney's methodically built and well-financed operation.

Huckabee's victory energizes his unlikely bid for the White House. But the new man from Hope now heads to New Hampshire, where voting takes place Tuesday, with little support in the polls and only a ragtag organization to mount a second come-from-behind victory.

For Romney, the defeat is a devastating blow to his careful strategy, conceived in Boston years ago, to win the early-voting states by outspending and out-organizing his rivals. He spent millions in Iowa alone, in part by tapping his personal investment fortune.

But the former Massachusetts governor is pulling out all the stops for a win in New Hampshire, where he has already begun to focus his fire at Arizona Sen. John McCain, not Huckabee. Romney left for Portsmouth on a chartered JetBlue flight before midnight.

Aides to Romney have been forced to wage a two-front war for more than a month. In Iowa, they engaged in a losing battle to overcome Huckabee's Southern charm and support among evangelical Christians. In New Hampshire, he faces McCain, whose connection to the Granite State runs deep and long, dating to his surprise victory over George Bush in 2000.

McCain's campaign collapsed this summer amid his steadfast support for the Iraq war and conservative anger over his support for immigration reform. But McCain has reinvented his campaign, becoming once again the maverick underdog that succeeded so well eight years ago.

Social conservatives in Iowa rallied around Huckabee after failing to find another Republican candidate to champion their positions on abortion, gay marriage, guns and immigration. Romney and McCain had unsuccessfully sought their support, but Romney was seen as coming too late to their thinking, and McCain was suspect because of his maverick streak. Another candidate, former New York mayor Rudolph Giuliani, who did not compete in Iowa, is anathema for his pro-choice position.

But other parts of the Republican establishment will not be cheering a Huckabee victory. He is viewed with suspicion by economic conservatives, who bristle at his anti-business message of economic populism and dislike his record of raising taxes in Arkansas. And his lack of foreign policy experience has been a concern for supporters of President Bush's national security policies. In speeches during the last 48 hours, Huckabee embraced the opposition from within his own party and cast himself as a fresh voice for change in Washington.

“If we win this vote, we will make political history like it's never been made in Iowa or America,” Huckabee told a crowd of almost 2,000 people at one of his final rallies in Des Moines Tuesday night.

Romney started organizing Iowa in 2004, hiring his first staff and beginning the process of courting voters with personal visits to the state. He spent $7 million on television ads, payments to local campaign chairmen, a veteran staff and dozens of mailings. He shot into the lead in May and stayed there until the beginning of December.

At the same time, the former Massachusetts governor lagged badly in national polls, earning only single-digit support while McCain, Giuliani and former Tennessee Sen. Fred Thompson at times surged into the lead.

But privately and publicly, Romney's advisers stuck to their strategy of investing heavily in Iowa and New Hampshire victories, recognizing Romney's lack of a national profile and believing that the pair of small states would propel him to the nomination.

“I started off this year in single digits, hardly known here in Iowa; in New Hampshire, likewise in single digits,” Romney said on the Today show Thursday morning. “And I've been able to put myself in a leading position in both states. So I'm tied for the lead here in Iowa, tied for the lead in New Hampshire. No one else is tied for the lead in both states.”

For much of the campaign, it had seemed like Huckabee was going nowhere. After raising only $1.5 million in the first six months of the year, he was lagging well-behind Romney and other candidates.

Aides had long felt his strong debate performances could help him win and get national media attention, but even that part of the strategy was not working well. “We knew he would do well in the debates if they ever called on him,” said Bob Wickers, a top aide.

So instead, the Huckabee campaign invested heavily in the straw poll held in Ames in August. The campaign's field director, Sarah Huckabee, the candidate's daughter, spent five weeks organizing support there. Huckabee's second-place showing, helped by support among Christian conservatives, helped launch his surge.

Looking to further ignite Huckabee's Oval Office run, campaign manager Chip Saltsman sought an endorsement from actor Chuck Norris, an Internet phenomenon because of a satirical Web site about him and a conservative Christian activist with a wide fan base from his movies.

Norris initially demurred, but later endorsed Huckabee in his column on WorldNet Daily, a conservative blog. Saltsman called Norris again to see if he would appear in an ad with the governor. “I would be willing to do anything,” Norris told Saltsman.

The offbeat ad worked. In it, Norris called Huckabee a “consistent conservative,” while the candidate offered lines like, “When Chuck Norris does a pushup, he isn't lifting himself up, he's pushing the Earth down.”

Soon after, Romney aides began seeing evidence that Huckabee was succeeding in winning support in the Christian community, even before public polls caught the trend. Romney started blasting Huckabee for his support of a bill that would have allowed illegal immigrants to get breaks on college tuition and his record-breaking number of pardons while governor of Arkansas that included the release of 11 convicted murderers.

The attacks led to the most bizarre moment of the campaign: Huckabee announcing he would not run a negative ad that he had prepared against Romney, then playing it for reporters and television cameras, virtually ensuring it would be seen across Iowa.

In fact, a battle between Romney and Huckabee for the hearts of Iowans was never supposed to happen.

When the 2008 Republican nomination kicked off in early spring, it was McCain who looked like the odds-on favorite to challenge Romney for a victory in the first presidential voting, despite his opposition to ethanol subsidies and his decision to skip the state in 2000.

But McCain - who started speeches in Iowa by joking that he had “a glass of ethanol for breakfast” - was regularly berated about immigration by Iowa voters and by talk radio hosts who opposed the immigration deal McCain tried to broker in the Senate. The money for his campaign dried up and his campaign manager and other top aides quit.

McCain's troubles helped Giuliani establish himself as the national frontrunner for most of the year despite a record that is at odds with much of the Republican base. Giuliani has opted to largely skip Iowa and New Hampshire, waiting until the contest reaches Florida on Jan. 29 and the more than 20 states which will vote on Feb. 5.

Right after Labor Day, Thompson, too, entered the race, hoping to galvanize the social conservative vote. But his unenthusiastic style of campaigning never caught on, and he lagged in the polls.