Florida Gov. Ron DeSantis on Sunday dropped out of the 2024 U.S. presidential race and endorsed Donald Trump as the Republican nominee for the White House.

DeSantis' exit leaves Trump and former U.N. Ambassador Nikki Haley in a head-to-head race. DeSantis' sudden announcement came only about a week after the contest for the Republican presidential nomination opened in Iowa and two days before a primary vote in New Hampshire.

Republican presidential candidate Florida Gov. Ron DeSantis makes a speech in the suburbs of Des Moines, Iowa, on Jan. 14, 2024, a day before the nomination process for the presidential election in November formally begins, with Republicans in the Midwest rural state expressing their preferences at precinct meetings. (Kyodo) ==Kyodo

"I can't ask our supporters to volunteer their time and donate their resources if we don't have a clear path to victory," the 45-year-old governor, once regarded as a formidable competitor to Trump, said in a video that he posted to social media. "Accordingly, I am today suspending my campaign."

DeSantis' withdrawal will be a big boost to the former president, the dominant front-runner in the nomination race for the November presidential election, and could prove a negative development for Haley, who is battling to stem the 77-year-old's popularity by gaining more support from moderate Republicans and independents.

"So far, only one state has voted. Half of its votes went to Donald Trump, and half did not," Haley said in a statement following DeSantis' pullout. "We're not a country of coronations. Voters deserve a say in whether we go down the road of Trump and (President Joe) Biden again, or we go down a new conservative road."

Calling for a generational change, Haley, who turned 52 on Saturday, urged New Hampshire Republicans to vote for her in the primary.

Trump, meanwhile, speaking at a rally in New Hampshire, thanked DeSantis for endorsing him, saying, "He was very gracious."

"I appreciate that and I also look forward to working with Ron" to defeat Biden, Trump said. "We will have to get him out," he said referring to Biden, who is most likely to be the Democratic nominee in the presidential election.

DeSantis finished a distant second behind Trump in the Jan. 15 Iowa caucuses. After investing much of his energy and money in the Midwest rural state, the governor was polling in the single digits in New Hampshire before his withdrawal.

Former U.S. President Donald Trump speaks during a campaign rally in Manchester, New Hampshire, on Jan. 20, 2024, in the Republican nomination race for the November presidential election. (Getty/Kyodo)

Most opinion polls have shown about 50 percent of likely voters in the New England state primary favor Trump, while Haley, who placed third in the Iowa caucuses close behind DeSantis, remains stuck in the mid-to-upper-30 percent range.

In the days leading up to the primary, a number of former Trump rivals coalesced around him, including Tim Scott, the only Black Republican in the Senate, who pulled out of the presidential race in November.

If Haley does not exceed expectations in New Hampshire, Trump sealing the nomination for a rematch against Biden will appear inevitable.

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