Donald Trump set aside months of criticism and mockery of Ron DeSantis today, celebrating his onetime Republican rival as his newest supporter after the Florida governor ended his presidential campaign and endorsed the former President.

For Trump, it’s become a familiar ritual to welcome the backing of someone who tried to take him on. Nonetheless, it was notable at Sunday’s rally in New Hampshire to see Trump praise DeSantis without calling him “DeSantimonious” or “DeSanctus,” putting an end to perhaps the most bitter rivalry of Republicans’ 2024 campaign.

“I just want to thank Ron and congratulate him on doing a very good job,” Trump said at the outset of his remarks. “He was very gracious, and he endorsed me. I appreciate that, and I also look forward to working with Ron.” Trump described DeSantis as “a really terrific person”.

Earlier in the day, DeSantis said via video that he would be ending his campaign two days before New Hampshire’s first-in-the-nation GOP primary. But, Trump’s glee on Sunday night (US time) aside, it wasn’t the warmest of endorsements.

“It’s clear to me that a majority of Republican primary voters want to give Donald Trump another chance,” DeSantis said, offering matter-of-fact analysis through a forced smile, without adding plaudits for Trump.

“I signed a pledge to support the Republican nominee, and I will honour that pledge,” he continued, before adding a dig at the remaining contender, Nikki Haley. DeSantis described the former United Nations ambassador and onetime South Carolina governor as a stand-in for “the old Republican guard of yesteryear, a repackaged form of warmed-over corporatism”.

Seemingly unbothered by DeSantis’ approach, Trump struck a tone of camaraderie as fellow political combatants. “I will tell you it’s not easy,” Trump said on Sunday night in Rochester. “They think it’s easy doing this stuff, right? It’s not easy.”

Then Trump quickly moved on to his typical rally speech, mixing freewheeling attacks on President Joe Biden, the political media, “the deep state” and “warmongers” in Washington, and the criminal justice that has indicted him four times, with 91 felony charges pending in multiple trials.

Florida governor Ron DeSantis speaks during a campaign event. Photo / AP

He devoted more time to criticising Haley than to praising DeSantis, casting her as a tool of the political establishment he has flouted. He made sweeping promises of peace and prosperity, pledging without offering any detailed plans that he would reverse inflation and end Russia’s war in Ukraine. And he repeated his lies that his defeat to Biden in 2020 was due to fraud.

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A boisterous crowd at the historic opera house in Rochester laughed, chanted and roared throughout.

“The great silent majority is rising like never before,” Trump answered.

DeSantis joins other failed GOP hopefuls, including South Carolina Senator Tim Scott and entrepreneur Vivek Ramaswamy, in endorsing the former President. Trump critics Chris Christie, the former New Jersey governor, and Asa Hutchinson, the former Arkansas governor, declined to endorse Trump after suspending their campaigns; Hutchinson endorsed Haley on Saturday.

Brenda Moneypenny, a 64-year-old from Alton, waited in the cold for two hours to see Trump on Sunday night. Moneypenny, who whipped out her driver’s licence to prove her last name, said she has considered Haley, especially because of the chance to elect the first woman to the presidency. But the Republican-leaning independent said she never considered DeSantis.

Republican presidential candidate Nikki Haley, a former UN ambassador, speaks at a campaign event. Photo / AP

“Too flim-flamsy,” Moneypenny said of the governor. “He needs better campaign people. He doesn’t have anybody that’s doing him any favours right now.”

Ultimately, she settled on Trump: “Tried and true,” she said.

The former President seemed to revel in skewering DeSantis throughout the campaign, often making clear it was a personal grudge because he considered the governor’s decision to run in the first place an act of disloyalty. Trump endorsed DeSantis, then a congressman, in a competitive 2018 GOP primary for Florida governor. DeSantis went on to win the nomination and the general election. By the time DeSantis won a landslide reelection four years later, though, he was positioning himself for his own White House campaign.

As recently as November, Trump came to Florida and addressed a boisterous crowd at a state GOP meeting standing in front of a sign that read: “Florida is Trump Country.” That evening, Trump did not mention DeSantis until more than 30 minutes into his speech. Even then, it was to brag about polls showing his advantages over the governor.

“I endorsed him, and he became a rocket ship in 24 hours,” Trump said, claiming DeSantis had begged for his endorsement. “Now he’s like a wounded falling bird from the sky.”

Trump never did debate DeSantis or any other 2024 rival. He has said he wouldn’t until one proves they are a legitimate threat to him winning the nomination.

DeSantis concentrated his campaign in recent months in Iowa, where he finished in second place in last week’s caucuses — 30 percentage points behind Trump and barely ahead of Haley. Haley, meanwhile, has long prioritised New Hampshire as a potential springboard before her home-state South Carolina primary next month.

Donald Trump gives a thumbs up after speaking at a campaign event. Photo / AP

In Iowa, APVoteCast surveys of caucusgoers suggested DeSantis’ supporters were much more likely than Haley’s to consider themselves conservatives who would back Trump no matter what if he wins the nomination and faces President Joe Biden in November. If that trend holds in New Hampshire, then Trump could expect at least some boost from DeSantis dropping out, and whatever he gets could stretch out his margin and frustrate Haley’s ability to claim any momentum. Indeed, Trump’s aides have said they expect DeSantis’ support around the country will shift heavily to Trump.

Trump noted on Sunday that he won New Hampshire’s 2016 primary by about 20 points. He lost the battleground state twice in general elections.

In the closing hours of the New Hampshire campaign, Trump will be juggling his legal troubles with the demands of seeking another term. On Monday US time, Trump will be in New York at a civil defamation trial stemming from a columnist’s claims he sexually attacked her. Then he is scheduled to return to New Hampshire for an evening rally in Laconia.

“I don’t have to be there,” he said of the court proceedings. “I could use your prayers. But look, it is what it is.”

His first criminal trial, stemming from charges that he is responsible for his supporters’ January 6, 2021, attack on the US Capitol, is scheduled to begin the day before the Super Tuesday primary slate on March 5.

“It’s a disgrace,” Trump said.