“Also,he desperately needs a personality transplant,and to the best of my knowledge they are not medically available yet,” Trump added.

Until now,DeSantis had been relatively muted against the former president,raising concerns among some Republicans and donors that he might not have what it takes to take him on.

While polls show the Florida governor still has the best chance of defeating Trump in a primary race,his stocks have declined significantly since the midterms and polls suggest he is now almost 40 points behind him.

The vacuum has encouraged other candidates to enter the race. Among them are South Carolinapolitician Tim Scott,the only black Republican in the US Senate,who this week joined an ever expanding list of Republican primary candidates that already included Trump’s former UN ambassadorNikki Haley,former Arkansas governor Asa Hutchinson,entrepreneur Vivek Ramaswamy and conservative radio host Larry Elder.

The Republican primary contest is likely to heat up even more within days and weeks,with former vice president Mike Pence,former New Hampshire governor Chris Sununu and former New Jersey governor Chris Christie also considering taking on Trump for a shot at the White House.

DeSantis’ announcement was seen as a chance to reset the contest. During the session,which was moderated by Musk and Republican donor David Sacks,he talked up some of the policies he has pushed in Florida,such as scrapping critical race theory in schools,shunning mask mandates during the pandemic,and fighting Disney over so-called “Don’t Say Gay” laws banning classroom instruction on sexual orientation and gender identity in kindergarten through to the third grade.

“Our mantra in Florida is that the purpose of the schools is education,not indoctrination,” he said.

He also vowed to tackle the crisis at the US-Mexico border,telling listeners that if he was elected as president,he would declare a national emergency “on day one”,construct the remainder of the border wall,and reinstate a Trump-era policy requiring some asylum seekers to be sent back to Mexico to await immigration proceedings.

DeSantis was also good-humoured about the technical malfunction that plagued the start of his launch,telling Musk:“This is a great platform… a healthy democratic society needs a robust debate.”

On paper,DeSantis’ backstory is picture-perfect – captain of Yale’s varsity baseball team,ex-Navy,married to Emmy award-winning former TV host Casey DeSantis,who is often regarded as his “secret weapon”.

But he has also faced criticism for his confrontational style and hardline policies,which include banning abortions beyond six weeks,restricting the use of declared pronouns in schools,and curbing African American studies.

“I cannot think of a group that is not targeted or paralysed outside of his own identity group,” David Johns,executive director of the National Black Justice Coalition,told this masthead.

“The thing I struggle most with is this idea that the previous occupant of the Oval Office[Donald Trump] might be our best hope for preventing the governor of Florida from occupying the Oval Office and neither should be options.”

After the session,some were sympathetic to DeSantis and praised his “historic” decision to use an audio talk session to launch his candidacy.

“The @RonDeSantis event just wrapped. He did 75+ minutes on pure policy. Trump could never do that,” tweeted former Trump chief of staff Mick Mulvaney.

Others,however,were far more scathing. “Ron DeSantis’ botched campaign announcement is another example of why he is just not ready for the job,” said Karoline Leavitt,spokeswoman for Make America Great Again Inc,a pro-Trump super PAC.

“The stakes are too high,and the fight to save America is too critical to gamble on a first-timer who is clearly not ready for prime time.”

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