If the New Hampshire primary goes as widely expected, Mitt Romney should emerge the winner among the candidates for the Republican presidential nomination. For weeks, polls in the state have shown him with a commanding lead.
But the 2012 campaign season has already delivered some surprises. Maybe New Hampshire will provide the latest in the series of unexpected twists?
Each remaining candidate, with the exception of Texas Gov. Rick Perry who decided to abandon New Hampshire to make his stand in South Carolina, has something to achieve Tuesday to be able to credibly claim victory. Here's what they need to do:
Mitt Romney — The former Massachusetts governor has the home field advantage in New Hampshire since he was once chief executive of the state next -door.
Also, he's essentially been campaigning in New Hampshire for at least the past six years, having run for president in 2008 and prepared the ground for that run before that.
Thus, Romney needs to win, and big. Any victory of less than 10 percentage points will likely be considered by media types as a weak showing, considering in polls he had more than a 20 percentage point lead over his nearest rival. It will make him look more vulnerable.
Rick Santorum — The near-winner of the Iowa caucuses, Santorum would be helped immensely by coming in the top three in the New Hampshire primary, preferably in second place. It would prove that Iowa wasn't a fluke.
That would be an astounding turnaround for Santorum, who, before the Iowa caucuses, has been polling in New Hampshire in the low single digits. After Iowa, his support surged in New Hampshire to double digits.
A strong showing could fire up social conservatives and Tea Party voters in the states to come, including South Carolina. It would also continue the former U.S. senator's momentum and his ability to raise money and attract plenty of free media.
Ron Paul -- The libertarian Texan is polling well in the "live free or die" state, with several polls showing what appears to be a last-minute surge. If Paul can do as well as some of the latest polls indicate he might, that would energize his base.
That doesn't mean he would be on his way to the GOP nomination. The likelihood of a majority of Republicans voting for Paul as their party's nominee is low, to put it politely, and Paul has even said publicly he doesn't expect to be the nominee.
But an upset win in New Hampshire or a strong second place showing would certainly give Paul the attention he seeks to expose his ideas to a mass audience.
Jon Huntsman — The former Utah governor and U.S. ambassador to China has the most riding on Tuesday's results. He has staked his entire campaign on the Granite State, moving his campaign headquarters there from South Carolina to show his commitment to the first-in-the-nation primary.
Tuesday night will test the wisdom of that move. After his single-minded focus on New Hampshire, if Huntsman doesn't wind up among the top three vote-getters, it will be a grievous blow and likely will be lights out for his campaign.
Newt Gingrich — The former House speaker had his turn in the front-runner spotlight in December, when he surged to the top of the Republican primary field. But a barrage of negative ads by Romney's superPAC allies and the Paul campaign knocked Gingrich from that perch.
Gingrich has to hope that the hits Romney has taken in New Hampshire have damaged the front-runner so much that it makes voters in the coming primaries look at Gingrich as an alternative.
If Gingrich can come close to the vote count of whoever comes in third place in New Hampshire, or if he emerges in the top three himself, that would likely be enough to give him some lift headed into South Carolina.