Former Maryland Gov. Larry Hogan has endorsed former South Carolina Gov. Nikki Haley for the GOP presidential nomination, shutting down rumors the anti-Trump Republican would make a third-party run for the office himself.

Hogan’s endorsement on Sunday comes just one day before the Iowa caucuses, where the 2024 presidential candidates will try to convince the state’s voters to choose them as the party’s representative in the general election. With the caucuses serving as the party’s first primary event, candidates hope a high ranking in Iowa will propel them forward for the remainder of the race.

Speaking on CNN’s “State of the Union,” Hogan said he thinks it’s “pretty clear” Trump will take first place in the Iowa caucuses. The final pre-caucus Des Moines Register/NBC News poll showed that nearly half the responders who consider themselves likely caucus-goers plan to support the indicted former president, while Haley sits at 20% and Florida Gov. Ron DeSantis at 16%.

“I think that’s not a big surprise. I don’t think it matters that much because, for the past 24 years, the winner of the Republican Caucus in Iowa has not been the nominee,” he said. “So it’s really about the fight for second place, and Ron DeSantis has put all the marbles on Iowa and spent all of his time and money, and seems to be going in the wrong direction.”

The former Maryland governor stressed that he believes Haley has the momentum to become the Republican Party’s nominee in November. Second place in Iowa on Monday night could lead her to potentially win next week’s primary in New Hampshire, where Hogan said she’s only trailing behind Trump by single digits.

“I think that that’s a real possibility, if she could potentially come in second place in Iowa, move on to New Hampshire,” he said. “It’s possible she could win, which would put her in a much better position when she moves into her home state of South Carolina.”

Hogan has become one of Donald Trump’s fiercest critics, declining last year to run for the GOP nomination if it meant another candidate could have a better chance at challenging the former president in 2024. The former governor has said that he did not vote for Trump in the past two presidential elections.

Last month, Hogan stirred speculation that he may enter the race when he resigned as co-chair of the third-party movement No Labels. Hogan told The Associated Press of his resignation just one day after former New Jersey Gov. Chris Christie, who is also vocally opposed to Trump, bowed out of the Republican primary race.

“I have been saying since last spring, when I made the decision not to run, that I really did not want to see a multi-car pile-up that would just enable Donald Trump. I think we want to have the strongest possible nominee in November,” Hogan said. “Polls show that that is Nikki Haley ― that she’s 17 points ahead of Joe Biden, and it’s a tossup with Trump and Biden, and DeSantis is losing.”

“So yes, I think it’s time for the party to get behind Nikki Haley,” he continued. “My friend Chris Christie dropped out of the race in New Hampshire. I appreciate his effort. But I believe that Nikki Haley is the strongest chance for us to put forth our best possible candidate for November.”