The Mike Huckabee phenomenon continues.

A new poll out of Iowa shows the former Arkansas governor and Republican presidential candidate with a 2-to-1 lead over former Massachusetts Gov. Mitt Romney, his largest margin to date.

The Newsweek poll showed Huckabee with 39 percent support among likely Republican caucus-goers, and Romney with just 17 percent in Iowa.

But the sampling group is small, which could account for why the results are out of line with other recent Iowa surveys. The poll, taken from Dec. 5-6, was based on phone interviews with 275 likely Republican caucus-goers. The margin of error was 7 percent.

Other recent polls show Huckabee, a Southern Baptist minister, making it into first place in Iowa, but not by so wide a margin. A new AP poll had Huckabee in second place nationally, behind former New York City Mayor Rudy Giuliani.

But among the 540 total Iowa Republican voters surveyed in the Newsweek survey, Huckabee still retained a strong lead, with 34 percent over Romney's 20 percent.

Romney was once the clear front-runner in Iowa, but Huckabee has come from relative obscurity to challenge him, with less than a month to go until the Jan. 3 caucuses.