Mr Trump already held a double-digit lead in many opinion polls taken in New Hampshire before Mr DeSantis’ exit. Most surveys suggest a majority of the Florida governor’s supporters view Mr Trump as the next best option.

At a rally in Laconia, New Hampshire, on Monday night Mr Trump said: “If you want a losing candidate who puts America last, vote for Nikki Haley.”

He told the crowd that “globalists and radical left communists” were convincing liberals to vote for her in the Republican primary.

“They want to run against her because she’s so easy to beat,” he added.

Most voters in New Hampshire will cast their ballots during the day on Tuesday but in tiny Dixville Notch, a handful of people voted at midnight in a decades-old tradition. All six registered voters in the resort town chose Nikki Haley over Donald Trump.