Co-chair of the state's congressional delegation Vern Buchanan became the eighth Florida representative to come out in support of the former president, announcing his endorsement on Wednesday hours after a personal call from Trump.
"If we want to get our economy back on track, Donald Trump is just the guy to get it done," Buchanan said.
Trump launched a bid for the 2024 Republican nomination in November, and polls show he is leading the field of declared and as-yet undeclared candidates.
DeSantis is expected to launch a run and is in second position in polls.
The string of Trump endorsements, including four in Florida and five in two other states this week, have come as DeSantis faces a barrage of insults on social media and attack ads from Trump's camp.
"When your calling card is Florida and folks in your own backyard defect that is never a good sign," said Ford O'Connell, a Republican consultant who was a Trump campaign surrogate in 2020.
"They have the DeSantis campaign in a vulnerable position."
DeSantis's team had asked members of Florida's congressional delegation to hold off announcing any endorsements, according to a person familiar with the effort.
Only one, Laurel Lee, stuck with DeSantis, announcing her endorsement on Tuesday.
Trump contacted the representatives personally, inviting them to a dinner at his Mar-a-Lago resort on Thursday night.
A DeSantis aide declined to comment.
A source familiar with DeSantis's thinking said the wave of endorsements had not persuaded the governor to accelerate his timetable for a presidential announcement.
DeSantis is expected to make clear his intentions after the Florida legislature wraps up its session early next month, followed by a more formal campaign launch in June.
DeSantis, the source said, is currently limited by law as to what he can do as a non-candidate and can't explicitly ask for endorsements.
"We haven't gotten started yet," the person said.
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