Millions of dollars have been spent on ads, thousands of speeches have been given, and hundreds of boxes of pizza consumed…all leading up to this. The Iowa Caucus. The kick-off contest of the 2012 GOP Presidential primary has arrived. With a field more fluid than any time since Gallup has been polling, there still remains big questions about how it will all turn out today.

The Iowa Caucuses are tough to poll. They are a relatively low-turnout event that allows Democrats and Independents to change their registration at their caucus site, making a likely voter model hard to accurately build. Regardless, it's instructive to look at the RealClearPolitics average to get a sense of the race. As of today it has Romney up top at 22.8, Paul at 21.5, Santorum at 16.3, Gingrich at 13.7 and Perry at 11.5. Bachmann and Huntsman are mired in single digits. 

But the RCP averages don't tell the story of the last minute shifts.

With Rick Santorum's recent Iowa surge, every candidate in the field, except for Jon Huntsman, has spent time as the leading anti-Romney candidate. The question around Santorum's rise is whether it can match Mike Huckabee's from 2008. Seeing that Santorum has Jim Bob Duggar of "19 Kids and Counting," whereas Huckabee had Chuck Norris, it's probably safe to assume Santorum's surge is likely to fall short of the bass-playing former Arkansas Governor.

But it is coming at exactly the right time. Santorum's polling numbers more than doubled over the four days of the Des Moines Register poll conducted by Ann Selzer, and he was only one point behind Romney in PPP's Iowa poll released on New Year's Day. 

While it comes at the right time for Santorum, he is still a relatively unknown entity in the field, meaning many folks will Google him to find out more. That's not a good thing for Santorum. [Don't do it at work]

Ron Paul's numbers appear to have receded a little bit under the field's assault on his wacky foreign policy views. But his organization is the strongest of any campaign in the Hawkeye State, and his supporters the most fervent, meaning he still has a decent shot of winning tonight, as those two factors have an outsized impact in low-turnout caucuses. After all, the turnout is not likely to surpass 5% of Iowans. 

Rick Perry and Newt Gingrich appear to be dueling it out for fourth place, a position that will give them an excuse to keep fighting towards the South Carolina primary. With Romney dominating in New Hampshire, both Perry and Gingrich seem set on making South Carolina a deciding contest. But to get there, one of these two campaigns needs to salvage a respectable finish today.

Romney is one lucky SOB. After watching Republicans flirt with every other campaign but his own, Romney appears to be in the perfect position to take advantage of a fractured field. While his staff has expertly managed expectations of Iowa all year, his recent leading of the highly-influential Des Moines Register poll, coupled with his statement in Iowa yesterday that "we're going to win this thing," has upped the ante for the former Massachusetts Governor today.

Should he win Iowa, he could effectively end the nomination fight today. It's not that the race will end automatically, but pundits will point back to an Iowa win as when Romney basically ended the race. No Republican in modern times has won the nomination without winning either Iowa or New Hampshire, and Romney is considered a near-lock in the Granite State primary, taking 41% in the latest NH Journal poll. 

All of this is to say…no one knows. Romney is far from beloved and momentum matters, meaning Santorum could take a surprise spot atop the field today.

In the respected Des Moines Register poll — which pretty much nailed the 2008 Iowa Dem Caucus results — 41% of respondents said they are still uncommitted to a candidate.

But this is why we love politics. We'll just have to wait to find out.

Check back at the Peak today for the most up-to-date results available. The Caucuses begin at 6 pm MST and results are expected by 9 pm MST, but likely earlier.