In 2020, the general election polls missed Trump's support in key states, and the election came down to the wire. So far in 2024, though, polls don't seem to be understating Trump support. We'll see if that continues to hold.

—Dan Hopkins, 538 contributor

Something I’ve been turning over in my mind is whether Trump is more similar to an incumbent president seeking his party’s renomination, or to a candidate pursuing the nod in an open field. Trump has already been nominated twice by the GOP, and, obviously, occupied the White House for four years, making him perhaps one of the best-known people in the world. In that sense, he has a lot of the advantages of an incumbent. And it’s worth noting that some of the other presidents who have pursued non-consecutive terms, like Grover Cleveland and Theodore Roosevelt, also used the tools at their disposal — especially their ability to communicate with the public — to try to dominate their parties.

It matters for how we think about the eventual result. If Haley finishes with a strong second, that’s the kind of result that’s pointed to real vulnerability with past incumbents in New Hampshire. As Dan Hopkins pointed out earlier, competition in New Hampshire foreshadowed Lyndon B. Johnson’s decision not to run for reelection in 1968. George H.W. Bush was “jarred” in 1992 by Pat Buchanan taking 40 percent of the New Hampshire vote. And Gerald Ford had a narrow win over Ronald Reagan in 1976 in the vote totals, previewing not only a tough general election, but also brewing divisions in the GOP ranks.

This has implications for Biden as well, who is projected to win New Hampshire, despite not officially being on the ballot.

—Julia Azari, 538 contributor

DeSantis and Haley were vying to be the last opponent standing to Trump, and with DeSantis suspending his campaign over the weekend, Haley got her wish. An interesting side-effect is that we now have more of an ideological race. In a November 2023 survey, I found that Republicans evaluated Trump and DeSantis as similarly conservative. Haley, however, they saw as more moderate. So with DeSantis's departure, we have a clearer ideological divide.

—Dan Hopkins, 538 contributor

Trump tonight did something no Republican presidential candidate has done since President Ford in 1976: win both Iowa and New Hampshire in a contested primary. As I've been saying for a while, Trump is effectively the incumbent in this process — much in the same way that Ford was an incumbent with an asterisk in 1976. (He was the sitting president, but nobody had voted for him for anything.)

—Jacob Rubashkin, Inside Elections

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