New Hampshire primary 2024: What to expect from the Trump vs. Haley matchup — and why it matters

Tuesday's primary in New Hampshire is former South Carolina Gov. Nikki Haley's best — and perhaps last — chance to change the direction of the Republican presidential primary.

Former President Donald Trump scored an easy victory in last week's Iowa caucuses, winning with more than 50% of the vote.

If the polls are right, he’s on track to win again by a large margin in New Hampshire — which could knock Haley out of the race and mean he’s the only major candidate left running for the Republican nomination for president.

He would also be the first Republican candidate for president to win both Iowa and New Hampshire since 1996, when Bob Dole cruised to the GOP nomination.

Why all this matters

The stakes are extremely high.

If Haley can come close to Trump in the primary, then she will be able to more credibly claim that this is a competitive two-person race.

If Trump wins by a big margin, however, it’s hard to see anyone stopping him from being the Republican candidate for president.

There are some reasons to be hopeful for Haley. She has gained momentum in New Hampshire over the past four months, rising from single digits to nearly 40% support today in the polling averages.

Polling averages are seen as the best way to gauge a candidate’s support ahead of an election. This is because they minimize the impact of what are called “outlier” polls that don’t match the trends that other surveys are finding.

Haley also enjoys the support of the state’s Republican governor, Chris Sununu, who has been campaigning for her.

The most recent polls, however, have found Trump growing his support following his blowout victory in Iowa last week, even as Haley has crept up in the polls as well.

Over the last few weeks, Trump’s polling average has gone from 43% up to 54%, while Haley’s has risen from 29% to 37%.

After Florida Gov. Ron DeSantis ended his candidacy on Sunday and endorsed Trump, it left another 7% or so of the vote up for grabs.

Why New Hampshire is different than Iowa

For over 40 years, Iowa and New Hampshire have held the first two Republican nominating contests. Yet they very rarely vote for the same GOP candidate.

One thing New Hampshire has in common with Iowa is that it is overwhelmingly white, with little racial diversity. That's a big reason why Democrats have changed their primary process to allow other states to play a bigger role in choosing the nominee.

But New Hampshire is not as politically or culturally conservative as Iowa, in line with the general contrasts between the Northeast and the Midwest.

Haley’s strength with moderate voters is a big reason she’s competitive in the state, which historically tends to support more centrist Republicans, such as Mitt Romney and John McCain.

Trump, however, did win the New Hampshire primary in 2016 after losing Iowa to Texas Sen. Ted Cruz.

There are also far fewer evangelical Christian voters in New Hampshire than there are in Iowa. Evangelicals tend to be some of Trump’s most fervent supporters.

And unlike in Iowa, voters who are not registered with either political party can vote in the New Hampshire primary. In fact, this group makes up the largest group of registered voters there.

There are roughly 300,000 registered Republicans and about the same number of Democrats eligible to vote. But there are about 400,000 unaffiliated voters registered and able to cast ballots in next Tuesday’s primary.

How to understand the results

If Haley loses to Trump by a margin that is considered to be a "landslide" — in this case, a solid double-digit victory in line with the polls — many pundits and lawmakers are sure to say that she no longer has a shot at the Republican nomination.

A Boston Globe/Suffolk University poll released on Friday showed Trump with 52% support in the primary, followed by Haley at 35%. If that is the result Tuesday, it could be interpreted by the press and the public as another overwhelming Trump win.

And if that’s the case, many will declare the race for the Republican nomination to be effectively over.

The closest Haley has been in any poll in recent weeks is 39% to Trump's 50%, in a CNN/University of New Hampshire survey released Sunday.

Even that poll shows Trump gaining steam, compared with the last CNN/UNH poll released earlier this month, which had Trump’s support at 39% to Haley’s 32%.

It seems likely that Haley will need to finish within single digits of Trump to claim that the race is still competitive.

What happens after New Hampshire?

The next contests will technically be in Nevada, which is bizarrely holding a primary on Feb. 6, followed by a caucus on Feb. 8.

But given the convoluted nature of what Nevada is doing — Haley is the only major candidate in the primary, while Trump chose to compete instead in the caucus — the next big contest will be the South Carolina primary on Feb. 24.

A big Haley loss in New Hampshire could set her up for embarrassment in the state where she was a popular Republican governor from 2011 to 2017. Trump is popular in South Carolina and is polling around 50% in the primary. Haley has shown some momentum there, doubling her support from 10% in September to just above 20% now.

But only a strong showing in New Hampshire is likely to give Haley a shot in South Carolina.

A competitive showing in South Carolina would signal a real race, ahead of Super Tuesday on March 5, when 14 states, including Alabama, California, Massachusetts, Texas, Vermont and Virginia, will hold primary elections.