In the latest Suffolk University/Boston Globe/NBC 10 Boston tracking poll, primary voters in New Hampshire who plan to vote for Trump were surer of their choice than voters for any other candidate. Eighty-one percent of Trump voters said they were not at all likely to change their mind, compared with 68 percent of Haley voters.

—Mary Radcliffe, 538

According to data collected by 538’s Mary Radcliffe and Cooper Burton, through yesterday, Haley had held 77 public, in-person campaign events in New Hampshire since she jumped into the presidential race last February. By contrast, Trump held only 17 events in New Hampshire between yesterday and his campaign announcement in November 2022.

Those numbers hint at the very different approaches to campaigning that the two candidates have taken in New Hampshire. Haley has crisscrossed the state trying to meet — and personally convince — as many voters as possible, while Trump has largely eschewed retail politics, instead relying on his popularity and media attention to garner votes. (And it works for him — he won Iowa in dominating fashion despite not campaigning very much there, either.)

New Hampshire also accounts for a much greater share of Haley’s total campaign events (39 percent) than of Trump’s (17 percent) — or for that matter most of the dropped-out presidential candidates’. That’s a reflection of how central New Hampshire is to her hopes of winning the nomination. (She even suggested as much at one of her town halls there, when she declared that “Iowa starts” the presidential race, but voters in New Hampshire “correct it.”) She absolutely must win here to have a shot, and her campaign schedule has reflected that.

—Nathaniel Rakich, 538

Last week I was in New Hampshire and sat down with Trump, DeSantis and Haley supporters to talk about why they’re voting for their chosen candidate. The Haley supporter, who voted for Biden in 2020, said that if Haley does not win the primary, she will vote for Biden or independent candidate Robert F. Kennedy Jr. in the fall. The DeSantis supporter told me he was committed to voting for Trump if he wins the primary, even if the former president is convicted of a felony before Election Day.

Immigration was the No. 1 issue for the Trump and DeSantis supporters, while leadership qualities were most important to the Haley supporter. Although these are only three people and not a representative sample like a poll, the themes I heard were reflective of the kinds of trends we’ve seen in issue polling in New Hampshire, which Monica has written about and mentioned earlier. If you want to hear straight from some New Hampshire voters themselves, check out the conversation here:

—Galen Druke, 538

The 2016 Republican nomination race was a far more crowded affair, but the New Hampshire primary that year can still tell us something about tonight. Eight years ago, Trump won with just 35 percent of the vote, but he carried most cities and towns in the Granite State because the vote was heavily fragmented. (Like in much of New England, New Hampshire’s municipalities, not counties, are the more important administrative divisions.) Overall, six candidates won between 7 and 35 percent statewide, and the next-closest contender was John Kasich, who won only 16 percent.

Looking at the 2016 map, the areas that Trump carried with less than 40 percent — colored pink or light purple — will hold the key to tonight’s result. This is especially true of areas in the south-central to southeast portion of the state, which produced about three-fourths of the _total_ 2016 Republican primary vote. We’ll want to see to what degree Trump has won over Republicans in these areas — and just how many independent voters show up, as the polls suggest they are more likely to prefer Haley.

One key area to watch will be the Seacoast, New Hampshire’s southeastern corner. This part of the state has many affluent and highly-educated towns where Kasich ran just behind Trump, such as Portsmouth and Stratham. To have any chance of an upset, Haley will need to perform strongly here, and hope that the region’s Democratic-leaning independents decide to participate in the GOP primary (much of the area is strongly Democratic). Haley would also need to hold down Trump’s margins in the most vote-rich part of the state, the south-central Merrimack Valley, which includes New Hampshire’s two largest cities — Manchester and Nashua — while also making inroads in highly-educated towns in the same vicinity, such as Bedford and Amherst. At the same time, the southeastern part of this region was much more strongly pro-Trump in 2016, so the degree to which he can run up the score in places like Salem will be important.

Moving slightly north, the capital of Concord is solidly Democratic, but it still cast the third-most GOP primary votes after Manchester and Nashua in 2016. Trump won less than 30 percent there, so it’s another must-watch spot. To the northwest, the areas where we’d largely expect Haley to win — and she needs to win big — are highly-educated areas along the Connecticut River (the Vermont border) such as Lebanon and Hanover (home to Dartmouth College), which Kasich carried eight years ago.

—Geoffrey Skelley, 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