President Trump gestures to a cheering crowd on the tarmac as he arrives on Air Force One at Palm Beach International Airport on Friday. He plans to spend the holidays at his Mar-a-Lago Club. (Carolyn Kaster/AP)

President Trump on Friday unexpectedly weighed in on the 2018 governor's race in Florida, talking up the potential candidacy of U.S. Rep. Ron DeSantis (R-Fla.), a tea-party conservative and an outspoken critic of special counsel Robert S. Mueller III's investigation into ties between Russia and the Trump campaign.

DeSantis, who recently introduced Trump at a campaign-style rally in Pensacola, is poised to join a competitive Republican field in the race to succeed Gov. Rick Scott (R-Fla.), who is term-limited.

If he runs, DeSantis would likely join two hopefuls with closer ties to the Republican establishment: Florida Agriculture Commissioner Adam Putnam, who previously served a decade in Congress, and Florida House Speaker Richard Corcoran.

Another GOP candidate, Jack Latvala, recently announced his resignation from the state Senate as the result of a sexual harassment scandal and is expected to exit the race.

"Congressman Ron DeSantis is a brilliant young leader, Yale and then Harvard Law, who would make a GREAT Governor of Florida," Trump said on Twitter. "He loves our Country and is a true FIGHTER!"

The tweet was sent out shortly after Trump landed in Florida en route to his Mar-a-Lago estate, where he is spending the holidays.

It appears the tweet was prompted by a Fox News segment featuring DeSantis that was playing on televisions in the cabin of Air Force One toward the end of the flight.

A White House official said DeSantis had been working Trump hard for an endorsement "on several fronts."

This official, who requested anonymity to speak more candidly, said Trump personally likes DeSantis but "has no idea who else is in the race or what it looks like."

The decision was not particularly strategic, this person said, and highlights some of the flaws in the president's political operation.

DeSantis, 39, accompanied Trump on Air Force earlier this month to the rally in Pensacola, where he introduced the president and borrowed several of his rhetorical flourishes, including "fake news," "drain the swamp" and "making America great again."

"This guy is working his tail off for you guys and for the American people," DeSantis told the crowd.

In a statement Friday, DeSantis said he was "grateful to have the President's support and appreciate what he has done — from appointing great judges to recognizing Jerusalem as Israel's capital to signing a pro-growth tax cut — to get our country back on track. As an Iraq veteran, I'm especially appreciative of his efforts to support our military and our veterans."

In Congress, DeSantis put forward a measure last summer that would have halted funding for Mueller's probe after six months and limited his investigation to matters that occurred after June 2015, when Trump launched his campaign.

DeSantis has criticized the probe into possible collusion with Russia as a "fishing expedition."

John McKager "Mac" Stipanovich, a longtime Florida Republican consultant, said Trump's shout-out on Twitter could give DeSantis a boost in a field where the well-funded Putnam is considered the front-runner.

"His Trump cred will put him in good stead," Stipanovich said. "DeSantis would be a viable candidate in a Republican primary if he can raise the money."

But Stipanovich added that being too close to Trump could hurt the GOP nominee in the general election in a state that Trump carried last year but where more voters disapprove of his job performance than approve, according to recent polls.

"He may be eating poison candy from which he'll die in November," Stipanovich said of DeSantis.

DeSantis, who was elected in 2012 to Florida's 6th congressional district, announced in 2015 that he would run for the U.S. Senate seat held by Sen. Marco Rubio (R-Fla.), who initially did not file for reelection in 2016 because of his Republican presidential bid.

DeSantis withdrew from the race after Rubio ended his White House bid and announced he would run for reelection.

During his tenure in Congress, which ended in 2011, Putnam ascended to a leadership position and voted for changes to immigration policy and other issues that have since become liabilities in Republican primaries. As a gubernatorial candidate, he has been trying to position himself further to the right on several issues.

Trump, who plans to play an active role in the 2018 elections, has inserted himself into Republican primaries on other occasions.

In Alabama's GOP primary for Senate this year, Trump endorsed and held a rally for Sen. Luther Strange (R), an establishment candidate who lost to former judge Roy Moore. Trump enthusiastically supported Moore in this month's special election, which he lost.

Trump also traveled to South Carolina in October for a fundraiser to benefit South Carolina Gov. Henry McMaster (R).

McMaster, a stalwart of South Carolina politics for the past three decades, was elevated to governor in January when Trump picked Nikki Haley to serve as ambassador to the United Nations. McMaster is now facing a primary challenge from a well-funded candidate, lawyer Catherine Templeton, who has cast herself as the insurgent in the race.