According to polling conducted in December and January, Trump and Haley were about equally popular in the Granite State before the Iowa caucuses, with an average net favorability rating (favorable rating minus unfavorable rating) among primary voters of +20 and +22 points, respectively. However, in polls conducted since the Iowa caucuses, Haley's net favorability among New Hampshire Republicans has fallen notably, to an average of just +3 points, while Trump's has risen to an average of +32 points.

—Mary Radcliffe, 538

If you're looking for something to do before results start coming in and you love New Hampshire politics, might I suggest listening to our 538 Politics podcast from last week. I talked to two lifelong Granite Staters who research and report on politics in New Hampshire — Neil Levesque, director of the New Hampshire Institute of Politics at Saint Anselm College, and Annmarie Timmins, senior reporter at the New Hampshire Bulletin.

We talked about the competing coalitions in the current GOP race and also about some of the broader political trends in New Hampshire. It's a state where elections have remained very competitive over the years, but where Biden appears to be holding up well in hypothetical head-to-head polling against Trump in 2024.

—Galen Druke, 538

Haley has been on quite a tear in New Hampshire polls over the last two months. She stands at 36 percent in 538's final New Hampshire polling average, compared to 19 percent on Dec. 1, 2023. Just ahead of the Iowa caucuses, that surge had narrowed Trump's margin in the Granite State to a little over 10 percentage points, much lower than his average margin across the other states.

Since Iowa, however, Trump has also surged in New Hampshire, shooting up to 54 percent percent, his best number of the whole cycle in the state. He is now 18 points ahead of Haley. It's likely Trump gained some votes from Ramaswamy, who was ideologically closest to him and endorsed the former president on stage in Iowa after withdrawing following his poor performance there. It is also possible that Trump will get a last-minute bump from DeSantis's drop out and endorsement on Sunday that is not fully captured by the polls.

Haley hitting, say, 40 percent in New Hampshire would be a feat. Across the polls we've collected, no other candidate even came close to that mark in any state. With such a showing, Haley could, somewhat credibly, claim a moral victory heading into Nevada and South Carolina next month. But, of course, moral victories do not win nominations.

—G. Elliott Morris, 538

It's been only eight days since Iowa's first-in-the-nation caucuses last Monday, but a lot has happened since then. On the night of the caucuses, businessman Vivek Ramaswamy dropped out of the race and endorsed former President Donald Trump, and Florida Gov. Ron DeSantis followed suit on Sunday. With former Arkansas Gov. Asa Hutchinson also leaving the race last week, former U.N. Ambassador Nikki Haley is Trump's last major competitor standing.

And everyone has their eyes on New Hampshire as potentially the only state where Trump has a realistic chance of losing. Haley has invested heavily in New Hampshire and has been suggesting since early December that today's race would be the start of a competitive two-person primary between her and Trump. She's got her two-person race, but whether it will be remotely competitive remains to be seen. Trump has only continued to consolidate party support since his Iowa victory, and anything less than a convincing win for him would be surprising.

So when might we know? First polls will close tonight at 7 p.m. Eastern, and last polls will close at 8 p.m., which is the earliest time we could have a race projection. But as we did last week (when Trump's victory was projected only 30 minutes after caucuses had begun), we will of course be sticking around no matter what happens to see how each candidate does across the state and discuss what it could mean for the rest of 2024.

And that's not all! Granite State Democrats also have a primary today, and it's a weird one — New Hampshire is violating Democratic primary calendar rules by holding it so early. As a result, President Joe Biden isn't campaigning or even on the ballot, but his competitors, Rep. Dean Phillips and self-help author Marianne Williamson, are. While Biden isn't expected to face serious competition for the actual nomination, his margin of victory today as a write-in candidate could be one early sign of Democrats' grassroots enthusiasm for the incumbent.

Bookmark this page for updates and analysis throughout the night!

—Tia Yang, 538

New Hampshire is one of the least religious states in the country. That might help explain why Trump’s closest competitor, Haley, has closed in on his lead a bit there: He’s at 54 percent to her 36 percent. While in 2016, evangelical Christians and regular churchgoers were reluctant to throw their support behind Trump, this key Republican voting bloc is now his solid base. And they’re missing in this first-in-the-nation primary.

In Iowa last week, Trump improved on his 2016 caucuses performance by 35 points in the most evangelical areas of the state, according to a Washington Post analysis. That’s just the latest evidence that evangelical voters are his to lose. In the 2020 general election, he won 59 percent of voters who attend church at least monthly, according to a Pew Research Center analysis. More than that, Trump moved many of his voters to identify as evangelical Christian, regardless of their church attendance habits.

Evangelicals remain one of the most motivated, active parts of the Republican Party nationwide, and, without that, Trump’s campaign might be missing a little steam. In addition to being less religious, New Hampshire residents have other identity markers that pull them further from Trump’s base. It’s one of the most educated states in the country, and has had an active Libertarian Party. In this respect, New Hampshire Republicans are a bit different from their fellow party members in other states. All of these factors might be giving Haley a small opening, but Trump is still favored to win.

Looking beyond that toward November, New Hampshire has voted for the Democratic candidate in every election save one since 1992. So while the eventual Republican nominee will have a shot, the less religious nature of New Hampshire might be a sign that the state is simply becoming more solidly Democratic like its New England neighbors, at least when it comes to presidential elections.

—Monica Potts, 538