MANCHESTER, N.H.--The polls heading into primary day in New Hampshire show a slight decline in support for Mitt Romney over the last several days, but not on a scale that puts his likely victory in any jeopardy.
If Romney's distance to his closest competitors remains what it has been in the latest polls, the Associated Press and the television networks will likely be able to project Romney the winner at 8 p.m. ET, when the last voters in the state cast their ballots.
Most of the attention on Tuesday night will fall on the race for second place. Ron Paul and Jon Huntsman are in a battle to woo late-deciding independent voters to their cause. "We're going to surprise the world," Huntsman said at his final campaign rally Monday night in Exeter, N.H.
Here are five things to watch as the returns begin to come in:
John McCain bested Mitt Romney in the New Hampshire primary by 5.5 percentage points in 2008, but he did so without winning the state's two most populous counties. Romney edged out McCain in Hillsborough County (Manchester and Nashua) and in Rockingham County (the southern tier of New Hampshire, heading East across the Massachusetts border towards Portsmouth on the coast).
Watch to see how much Romney is able to run up the score in these two counties. If he is not substantially beating his competition across this region, it will likely set off some alarm bells inside his campaign.
The Huntsman campaign is carefully watching what one adviser described as "the reverse L." Huntsman is seeking to swell his support along the Maine border and across the state to the West. Pay close attention to Merrimack County (home to Concord) to see if the much-buzzed-about Huntsman momentum is being realized in votes.
There are lots of college towns dotting the New Hampshire landscape, and those towns are likely to be at the heart of Ron Paul's support (Durham in the East, Keene in the West).
Much is always written about independent voters, especially here in New Hampshire where they make up nearly 41 percent of the 767,383 registered voters. In 2008, undeclared (that's what they call them here) voters made up 34 percent of the Republican primary electorate. McCain won 38 percent of them versus Romney's 30 percent.
Without a competitive Democratic contest to lure some of those independents, they are expected to make up an even greater share of the Republican electorate this time around. If Romney underperforms his 2008 take, that may be good news for Jon Huntsman, who is hoping to ride a wave of independent support to a surprising and strong second place showing.
However, independents alone cannot deliver a victory in the Republican primary. Watch to see if Romney improves upon the 33 percent share among registered Republicans he garnered in 2008.
Four years ago, 39 percent of Republican primary voters in New Hampshire made up their mind about which candidate to support in the final 72 hours of the campaign. That's a huge swath of the vote and the last three days have not been kind to Mitt Romney.
Late deciders will be critical in determining Romney's final number tonight. The news coverage in the closing days has been all about the attacks coming from his opponents on Romney's Bain record and his authenticity. His made-for-TV moment where he stated how he loves firing people who provide subpar services only adds to a late decider's voting calculus.
Newt Gingrich and Rick Santorum, the two candidates best positioned to wear the mantle of the conservative alternative to Mitt Romney, also happen to be the two Catholics (one by conversion) in the race.
There is a huge Catholic population in the Manchester area, but be careful about equating this religious group as socially conservative. New Hampshire Catholics tend to operate a bit more like swing voters than as voters who simply look to support the most faithful Catholic in the race. These are very different voters than the evangelical Christian bloc in Iowa.
Catholics made up 38 percent of the Republican primary electorate in 2008 and McCain and Romney split them evenly. Roughly one-third of those Catholics said they went to church weekly.
Although Santorum's social conservatism may not be the best match for the New Hampshire Catholic Republican voter, if he can win over a significant slice of these voters, it could help him gain back some of his momentum, which has greatly dissipated since his huge night in Iowa last week.
Make sure to watch the candidates' speeches to their supporters. If Huntsman does surge to second place, how will he lay the groundwork for moving forward to South Carolina? If Ron Paul places third again, will he offer up any indication about how he plans to crack that 20 percent ceiling of his?
Most important, watch to see if Romney takes his opportunity in the spotlight to get his campaign back on message and on course. He squandered his moment in Iowa by reverting to his traditional stump speech. If he emerges with a strong victory, he will have another big chance before a national audience to push back on the "corporate raider/out of touch CEO" message frame that his Republican (and potential Democratic) opponents have been building around his candidacy.
And Newt Gingrich and Rick Santorum's comments will likely be a preview of the intense and more negative campaign awaiting the candidates in South Carolina.
David Chalian is the Washington bureau chief for Yahoo News.
Read more coverage of the 2012 New Hampshire primary at Yahoo News.
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