The race in Iowa is shifting its focus as Barack Obama and Mike Huckabee lead a new poll.

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A Des Moines Register poll released Sunday found that former Arkansas Gov. Mike Huckabee is continuing his surge in Iowa, and for the first time has opened up a small lead over former Republican frontrunner Mitt Romney.

And on the Democratic side, Obama hs stepped into the lead for the first time, as Hillary Clinton slips into second place.

Romney and Clinton have both held the top spot in Iowa for months.

The Des Moines Register poll showed Huckabee in front with 29 percent and Romney with 24 percent. Rudy Giuliani trails with 13 percent, Fred Thompson awith 9 percent, and John McCain and Ron Paul each with 7 percent. Tom Tancredo has 6 percent. Even with the poll's 4.4-percent margin of error, Huckabee still has the lead.

While Huckabee leads the poll, he trails Romney in money and organizational strength. With limited resources, the future of Huckabee's bid relies on an Iowa win -- and the momentum and money that could come with it.

If beaten in Iowa, Romney still would be able to compete in New Hampshire, where he leads in polls and has a strong campaign. But a loss would severely set him back.

On Friday, he said he's not surprised the Iowa race tightened. "People have a lot of people to choose from, and as they get to know folks and find things they like about different candidates, that's what you'd expect," Romney said.

He is stepping up his criticism of Huckabee on taxes and immigration. His surrogates also now are arguing to social conservatives that Huckabee doesn't have the money and manpower needed to beat Giuliani, an abortion-rights backer, in contests beyond Iowa.

Among Democrats, Barack Obama got 28 percent, while Hillary Clinton had 25 percent and John Edwards had 23 percent. Other candidates were in single digits. More than half of likely caucus-goers in both races say they could change their minds. A chunk are undecided.

As Obama's position has strengthened, Clinton has stepped up her attacks.

Clinton assailed the Illinois senator on Sunday for a political action committee he controls that has contributed money to elected officials in early voting states. Asked by reporters if Obama's character was in question, Clinton said in Cedar Rapids, Iowa, "I'm going to let voters make that decision, but it's beginning to look a lot like that."

In Des Moines, Obama brushed off the spike in criticism. "I think that folks from some of the other campaigns are reading the polls and starting to get stressed and issuing a whole range of outlandish accusations," he said.

The Jan. 3 Iowa caucuses mark the first official vote in the 2008 presidential race.

Additional Resource:

• Des Moines Register