MANCHESTER, N.H. — Casting himself as an "unknown Southern boy," Mike Huckabee said Tuesday his third-place finish in the New Hampshire primary was good enough to sustain his Iowa-propelled candidacy for the Republican presidential nomination.

He pledged to forge ahead in hopes of doing better in coming contests.

"Tonight we're going to come out of here with continued momentum," Huckabee told supporters.

The former governor of Arkansas used his come-from-behind Iowa victory to catapult him out of the back of the Republican pack in New Hampshire.

He was never a threat to Tuesday's victor, John McCain, or to Mitt Romney, who finished second.

But he had hoped for a third-place finish to keep him breathing political oxygen as he heads into friendlier states.

"In Michigan, in South Carolina, in Florida ... what you helped us continue will be carried right on through, and it won't be long we're going to be able to secure the nomination and on to the White House and on to leading America," he said.

Polls in Michigan and South Carolina show him leading or in a tie for first place. Until now, his main rival had been Romney, but as he moves on he will have to compete more directly with McCain as well, who is also counting on Michigan and South Carolina to propel his campaign.

New Hampshire, unlike Iowa, is not a state with a large evangelical population.

Indeed, about a fifth of the New Hampshire GOP voters interviewed in exit polls said they were born again or evangelical voters, compared to the six in 10 who said so in last week's Iowa Republican caucuses.

Huckabee, an ordained Baptist minister, had roughly a third of the support of evangelicals, giving him a slight edge over McCain and Romney.

"We just sensed that we were going to do better than a lot of people thought that this unknown Southern boy could possibly do up here in New England," he told supporters assembled at a Manchester golf club.

While in Iowa, Huckabee had played up his religious values, most famously in a Christmas season ad where he spoke of celebrating the birth of Christ. But as he turned to New Hampshire, he instead stressed an economic populism and a political unification much like Democrat Barack Obama.

His ads in the state also focused on his economic record as governor, an attempt to neutralize independent ads against him that have characterized him as a tax raiser.

One group that has been a dogged Huckabee critic, the conservative free-market Club for Growth, said Tuesday it is spending $200,000 on an ad in Michigan mocking tax and spending increases enacted in Arkansas while Huckabee was governor. Huckabee and the Club for Growth have been emphasizing different sides of his economic record. He did advocate several tax increases while governor, but also signed a 1997 tax cut that was the largest tax cut in Arkansas history at the time.

His supporters on the stump ranged from home-schooling parents to supporters of his plan to eliminate the income tax and replace it with a national sales tax. Compared to his leading rivals, he has been operating on a shoestring budget.

"We thought that if we could finish in the top, we kept saying four or five, we'd feel pretty good about that, knowing just how tough it's been to try to break through. But tonight, you've given us so much more than we could have imagined just a few days or weeks ago," Huckabee said.