Just ask Santorum, the former senator who won the 2012 Republican caucuses -- weeks after Mitt Romney was initially judged the winner -- only to fall short in his pursuit of the GOP nod. Or Mike Huckabee; the former Arkansas governor won here in 2008, but failed to capture the nomination.
Not since George W. Bush claimed victory here in 2000 has the first-in-the-nation contest winner gone on to win the GOP nomination in a contested race.
And then there's the Ames Straw Poll, a heavily hyped event held months before the caucuses. The last two winners? Romney in 2007 and Rep. Michele Bachmann (R-Minn.) in 2011. Neither went on to win Iowa or the nomination the following year. In fact, of the six Straw Poll winners, only three have gone on to win the caucuses, and only two have won the GOP nomination. So, it's easy to see why some GOP leaders want to do away with it.
None of this is to say that Iowa doesn't matter at all. It does. Had Santorum not done so well here in 2012, his campaign against Romney would not have stayed afloat as long as it did.
"Iowa has the privilege of punching one, two, maybe three tickets to New Hampshire," said Rep. Steve King (R-Iowa), who later added, "It doesn't trouble me that Iowa's decision doesn't always end up in the White House because the process, I think, does stand out; not just first in the nation, but there's no other contest like this."
On the Democratic side, Iowa has mattered more in recent years. In the last three contested Democratic presidential primaries, the candidate who won Iowa went on to win the nomination.
President Obama's 2008 victory here was a defining moment in the campaign. By winning the heavily white and rural state, Obama showed the rest of the country that he could compete anywhere.
This much we know: Potential candidates will continue to travel to Iowa in the lead-up to 2016. And as we've argued time and again, no politician travels to the Hawkeye State by accident. So for the next two-and-half years, it's well worth keeping tabs on who's spending time here, and how often they are making the trip, because it will offer clues about who wants to run for president.
But on caucus night in 2016, remember that the victors may be enjoying only a temporary celebration.