This story has been updated.

Celebrity mogul Donald Trump endorsed former Massachusetts governor Mitt Romney in Las Vegas today.

“Mitt is tough, he’s sharp, he’s smart,” said Trump from the lobby of his Las Vegas hotel. “He’s not going to allow bad things to continue to happen to this country that we all love.”

Romney took the podium after Trump’s brief endorsement.

“There are some things you just can’t imagine happening in your life. This is one of them,” he joked, adding more substantively that the two agree on China policy. He called Trump’s endorsement “a delight,” adding that he was “so honored and pleased” to have the reality star’s backing. He quickly pivoted into a short stump speech; the whole event lasted only a few minutes.

“I think if he debates the way he’s been debating, I think he’ll beat Obama handily," Trump said of Romney in a brief meeting with reporters in the hotel lobby.

Earlier reports had suggested that Trump would endorse former House speaker Newt Gingrich. CNN first reported Trump’s plan to back Romney.

The endorsement, for all the media attention it has gotten, will most likely make little difference to voters. A January Washington Post-Pew poll found that nearly two-thirds of Republicans and GOP-leaning independents said a Trump endorsement would make no difference in their vote. Moreover, somewhat more said it would be more of a reason to oppose than to support a candidate (20 to 13 percent).

Donald Trump has once again inserted himself into the Republican race. (Richard Drew/AP)

Among all Americans, just 8 percent said they’d be more likely to vote for a Trump-endorsed candidate; more than three times as many said they’d be less likely to do so (26 percent).

Trump’s waning influence was on display in December, when he attempted to host his own presidential debate. Only two candidates agreed to attend: former Pennsylvania senator Rick Santorum and Gingrich.

Gingrich is the candidate in the field who most shares Trump’s pugnacious style. But Trump had praised Romney in recent days, calling him the “clear winner” in recent debates and saying his financial success is “a positive.” At the time, he was still mulling getting into the race himself.

It’s not clear that Trump’s endorsement would change the dynamic of the Nevada race much. Gingrich has suffered from poor organization in the Silver State and is behind Romney by 20 percent in polls.

It would seem appropriate for Trump to make his endorsement in Las Vegas, where he owns a 64-story hotel.

Washington Post polling director Jon Cohen contributed to this report.

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