NEWFIELDS, N.H. – Republican Gov. Chris Sununu of New Hampshire is expected to endorse former ambassador to the United Nations and former South Carolina Gov. Nikki Haley, multiple GOP sources confirmed to Fox News.

The endorsement by the popular governor of the state that holds the first primary and second overall contest in the Republican presidential nominating calendar is all-but-certain to occur when the two team up Tuesday evening at a Haley campaign event in Manchester, New Hampshire.

Sununu's political team released a media advisory early Tuesday morning announcing that the governor would join Haley and make remarks at a town hall at 6 p.m. ET at the McIntyre Ski Area in Manchester.

And in a statement to Fox News, the governor said "I look forward to joining Nikki at her town hall this evening - it's going to be a lot of fun!"


Sununu introduces Haley at New Hampshire town hall

Republican Gov. Chris Sununu introduces 2024 GOP presidential candidate and former ambassador to the United Nations and former South Carolina Gov. Nikki Haley at a town hall in Hooksett, New Hampshire, on Nov. 20, 2023. (Fox News - Paul Steinhauser )

The endorsement could potentially sway some independent and moderate voters who often play an influential role in New Hampshire's crucial presidential primary.

Sununu has long been a vocal critic of former President Donald Trump, the commanding front-runner for the 2024 GOP nomination as he makes his third straight White House run. 

The governor flirted with his own presidential bid before announcing in early June that he wouldn't seek the White House in 2024. Since then, he's said he would eventually endorse in the Republican nomination race and has teamed up repeatedly with many of the GOP contenders as they've campaigned in New Hampshire. 


In recent weeks, he's said that he had narrowed his endorsement choice down to three candidates – Haley, former New Jersey Gov. Chris Christie, and Florida Gov. Ron DeSantis.

Christie, who is once again spending most of this time and resources on New Hampshire as he makes his second White House run, returns to the campaign trail in the Granite State with two events on Wednesday. 

Christie and Sununu team up on the campaign trail in New Hampshire

Former New Jersey Gov. Chris Christie (left), a 2024 Republican presidential candidate, teams up with GOP Gov. Chris Sununu of New Hampshire at a town hall in Merrimack, N.H., on Nov, 9, 2023. (Fox News - Deirdre Heavey)

As he worked to land Sununu's endorsement, Christie has spotlighted that when it comes to Trump, he and the New Hampshire governor were on the same page.

"Who does he want standing across from Donald Trump when this gets down to a one-on-one? Who does he think can take him on in a direct way? Who’s been saying the same things as Chris Sununu has been saying for the last couple of years about Donald Trump, trying to move the party in a new direction? And I think I’m the person who has the clearest, strongest voice on that," Christie emphasized in a Fox News Digital interview a couple of weeks ago.

DeSantis, who is spending most of his time in Iowa, is expected back in the New Hampshire on Friday.

"What happens in New Hampshire will be significantly impacted by the outcome in Iowa, where the true Trump alternative will emerge. And when Ron DeSantis comes out in that position, he will be joined by over 60 New Hampshire state legislators who stand ready to take the fight to the establishment and their candidates of yesteryear to return power to grassroots conservatives," DeSantis campaign spokesman Andrew Romeo argued in a statement.

Sununu campaigned with all three candidates on the trail in New Hampshire just before Thanksgiving.

"Nikki’s done a great job. She’s been really pounding the pavement in terms of going to various parts of the state, talking to folks, letting them ask her questions," Sununu told reporters after teaming up with Haley in Hooksett, New Hampshire. "Her message seems to resonate."

Nikki Haley is introduced by Gov. Chris Sununu at a campaign town hall meeting in Merrimack, New Hampshire, on Sept. 6, 2023.

Nikki Haley is introduced by Gov. Chris Sununu at a campaign town hall meeting in Merrimack, New Hampshire, on Sept. 6, 2023. (Reuters/Brian Snyder)

Haley, who has enjoyed momentum in the polls in recent months, thanks in part to well-received performances in the first three GOP presidential primary debates, leapfrogged DeSantis for second place in New Hampshire and her home state, which holds the first southern contest. Christie stands in third place in most of the latest surveys in New Hampshire.

Haley also aims to make a fight of it in Iowa – the state whose Jan. 15 caucuses lead off the GOP nominating calendar – where the latest polls suggest she is close to pulling even with DeSantis for a distant second place behind Trump.


Early this past summer, at the New Hampshire GOP's annual cookout, Haley was introduced by Sununu. After exchanging a hug, Haley kicked off her comments to the crowd by saying, "You’ve got a great governor."

With a joke that elicited plenty of laughter, she said, "Governor, I very much worry about your health. What I’m thinking is, I don’t want you to over-stress. I don’t want you to get out there and do too much. So I think what’s best is, go ahead and endorse me now."

Haley was kidding, but in the ensuing months she's jokingly asked Sununu about an endorsement a handful of times.

Republican Gov. Kim Reynolds of Iowa early last month endorsed DeSantis. Since then, Reynolds has joined DeSantis at multiple stops on the Hawkeye State campaign trail. 

Iowa Governor Kim Reynolds Endorses GOP Candidate Ron DeSantis For President

Gov. Ron DeSantis speaks with Iowa Gov. Kim Reynolds during a campaign rally on Nov. 6, 2023, in Des Moines. (Scott Olson/Getty Images)

Sununu told Fox News Digital last month that his endorsement would also be much more than just a one-day announcement.

"If I get behind a candidate, I’m going to get behind a candidate," he emphasized.

And he later added that he'd put muscle behind his endorsement, "110%."

"That’s the fun part. Are you kidding? I’m not going to do an endorsement and sit on my hands. When I do an endorsement, it's going to be a six-, seven-, eight-, nine-week push, whatever it is, to really make sure folks know where we are. I tend to not leave anything on the table," he emphasized.

And Sununu, who's won election and re-election to four two-year terms as New Hampshire governor, said he'd help whichever candidate he backed "put together a ground game. I think we know how to do it pretty well here."

But he's also tempered expectations that his endorsement might move the needle in the Granite State, telling Fox News last month that "I’m never a big believer that endorsements matter as much as the press think they do."


Longtime New Hampshire-based Republican strategist Jim Merrilll, a veteran of numerous presidential campaigns, told Fox News the endorsement - which was first reported by WMUR - was "a big deal."

"There's no endorsement in New Hampshire you'd rather have. And it's clear he's going to use it early and often to support Haley."

"Chris Sununu is the Shohei Otani of New Hampshire politics. He's a remarkably gifted, best-in-class talent. He's our state's most successful and impactful Republican of his generation. So his endorsement of Nikki Haley makes this the best day of her campaign and gives her a heck of a clean-up hitter down the stretch," Merrill emphasized.

Neil Levesque, the executive director of the New Hampshire Institute of Politics at Saint Anselm College, told Fox News "it is always questionable whether endorsements matter but in this case, this is a game-changing endorsement."

"This is why," Levesque continued. "Sununu is one of the most talented communicators in politics. You combine that with his credibility and popularity in a state like New Hampshire and the fact that he’s going to basically go on the road and sell this to New Hampshire voters and make a persuasive argument for Nikki Haley, I think is going to move the needle."

But longtime New Hampshire based Republican consultant Mike Dennehy told Fox News "I think times have changed from the 1990s when endorsements by a governor made a significant difference."

"I expect Sununu will open some doors and he will make for a very good surrogate, but in the end I don't think it will make more than a one percent difference in this race," Dennehy, a veteran of numerous GOP presidential campaigns, said.

Sununu's backing of Haley comes a couple of weeks after she landed the endorsement of Americans for Prosperity Action, the political wing of the influential and deep-pocketed fiscally conservative network founded by the billionaire Koch Brothers. AFP Action has pledged to spend tens of millions of dollars and mobilize its formidable grassroots operation to boost Haley and help push the Republican Party past Trump.

Trump at rally

Former President Donald Trump leaves the stage at a campaign rally Saturday, Nov. 11, 2023, in Claremont, New Hampshire. (AP Photo/Reba Saldanha)

Trump continues to hold a very formidable and very large double-digit lead over Haley, DeSantis and the rest of the remaining field of rivals for the nomination in the latest polls in New Hampshire, Iowa, South Carolina, and in national surveys.


But Sununu said last month that Trump's "got a floor, but he’s also got a ceiling," 

"And when you look at the fact that well over 50% of the Republican core-based voter wants somebody else, the fact that in New Hampshire you can have independents that come out – I believe in record numbers – most of which won’t vote for yesterday’s news in terms of Donald Trump," Sununu argued.

The Trump campaign on Tuesday took aim at the New Hampshire governor.

"Sununu’s endorsement means nothing and does nothing for any candidate in this race," Trump campaign spokesperson Steven Cheung charged in a statement to Fox News. "The only endorsement in politics that matters is President Trump’s endorsement. Nothing will stop him from securing the nomination and beating Crooked Joe Biden and retaking the White House."

Fox News' James Levinson contributed to this report

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