SCOTT HORSLEY: And I'm Scott Horsley.
On the Republican side of the contest, it's come down to this. Mitt Romney has run more than 8,000 television ads in Iowa trying to convince GOP voters he should be their nominee. But with just hours to go before the caucuses, the former Massachusetts governor found himself in the tiny Mason City Airport yesterday trying to seal the deal.
Mr. MITT ROMNEY (Former Republican Governor, Massachusetts; Presidential Candidate): We're in a neck-and-neck race. I mean, we are on a razor-thin edge. I don't know who's going to be ahead in terms of the polls. But the difference as to who's going to actually win depends on who turns out.
HORSLEY: That's why candidates in both parties have been crisscrossing the state, and why a place like Mason City, with just 27,000 residents and a Mexican restaurant called Carlos O'Kelly's drew visits yesterday from not only Romney but GOP rivals Mike Huckabee and Fred Thompson as well.
Mason City resident Mike Forbes(ph) was among the voters Romney was trying to sway during a barnstorming tour of Iowa. He's leaning in Romney's direction. He likes the former businessman's plan to cut taxes on savings and investments. But Forbes also checked out Huckabee when the former Arkansas governor spoke in Mason City just a few miles away from Romney's event.
Mr. MIKE FORBES: Actually, I could support of those guys real easy. Yeah, I could vote for both of them, actually.
HORSLEY: For much of the last year, Huckabee was an also-ran in the Republican race, wildly outspent by better-funded opponents. But since November, he's held a narrow lead over Romney in some Iowa polls. He told supporters yesterday they have a chance to show America that Iowans can't be bought.
Mr. MIKE HUCKABEE (Former Republican Governor, Arkansas; Presidential Candidate): Nobody really thinks that it's possible to win a caucus or any election when you're outspent 20-to-1. You can prove the pundits wrong and the people right.
HORSLEY: Huckabee has drawn support from evangelicals and home-schooling activists, as well as some independent voters like Florence Klein(ph), who works in a natural food store.
Ms. FLORENCE KLEIN: Actually, I was expecting that I would be more attracted to some Democrats. So it's very unusual that I'm here.
(Soundbite of laughter)
Ms. KLEIN: I'm intrigued that if he's in a rock band and plays bass. I'm - he's just a fascinating human being.
HORSLEY: Unlike Romney, a governor's son who is catering to a traditional Republican base of social conservatives, fiscal conservatives, and defense hawks, Huckabee is more of a populist. When he talks about his humble upbringing, he sounds a lot like Democrat John Edwards.
Mr. HUCKABEE: My mother was one of the seven children in her family. She was the oldest and so she went to work early so she could help them. When she was a little girl, her family lived with dirt floors, outdoor toilets. And that's where my roots are.
HORSLEY: Huckabee joked yesterday about offering body-warming campaign buttons to caucus-goers who drag friends out in the cold, and about shoveling snow into the driveways of political opponents to keep them from getting out to caucus. The jokes may have been a warm-up for Huckabee's appearance on last night's Jay Leno show. That trip sparked a minor controversy when Huckabee had to cross a picket line of the show's still striking writers.
While Romney and Huckabee battle for the top spot in Iowa, John McCain is also hoping for a strong showing. The Arizona senator had largely ignored Iowa throughout the fall and early winter. But last night he had to push his way through an overflow crowd of supporters at his campaign headquarters outside Des Moines.
Senator JOHN McCAIN (Republican, Arizona; Presidential Candidate): I'm very grateful for you being here. I'm grateful for this expression of support. And I can tell you we've come a long way since I met the 1,203 pound pig named Big Red at the Iowa state fair.
(Soundbite of laughter)
Sen. McCAIN: And then enjoyed a pork chop on a stick, followed by a delicious deep-fried Twinkie.
HORSLEY: Back during fair season this past summer, McCain was all but written off. But he's shown new life in recent polls. Last night he spoke about fighting Islamic extremists and restoring faith in government.
Linda Kilsmayer(ph) of Johnston, Iowa was impressed.
Ms. LINDA KILSMAYER: I feel I can trust him. I don't feel like he's bashing anybody else, like some of them are doing already. And everybody gets tired of that.
HORSLEY: A strong third-place finish in Iowa could give McCain's campaign added momentum tomorrow when the focus shifts to New Hampshire.
Scott Horsley, NPR News, Des Moines.
RENEE MONTAGNE, host:
If you're a non-Iowan still scratching your head over how those caucuses work, find out at npr.org, where you can also read more about what's at stake there.
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