Mitt Romney and Donald Trump's relationship had all the permanence of a Las Vegas wedding.

Perhaps Romney said it best when he took to the podium that fateful day in February of 2012 to accept Trump's endorsement.

"There are some things that you just can't imagine happening in your life. Uh, this is one of them," the eventual Republican nominee said to laughter.

Now there's a lot of love lost — Romney made a rare speech Thursday to blast Trump as unfit for the presidency, calling him a "con man." And Trump has ridiculed Romney's failed presidential campaign.

Back in 2012, Romney was on the hunt for endorsements and votes ahead of the Republican caucuses in Nevada in a heated race for the nomination, trying to fend off the likes of Newt Gingrich and Rick Santorum.

That day's endorsement was a coup — from none other than The Donald himself.

"Being in Donald Trump's magnificent hotel and having his endorsement is a delight," Romney said with perhaps a telling grin. "I'm so honored and pleased to have his endorsement and of course I'm looking for the endorsement of the people of Nevada.

It was an epic event. Here's how The New York Times' Mark Leibovich summed it up with his lead on that day's story:

"Not since Don King's last solo press conference had so much fabulous hair adorned a single Las Vegas venue."

It's not clear who exactly told Romney that winning the endorsement of a New York billionaire in his Las Vegas hotel was the way to win Nevada. But there he was.

Channeling Trump, Romney promised to fight the "cheaters," like China. "He's one of the few people who has stood up and said, 'You know what, China has been cheating. They've taken jobs from Americans. They haven't played fair,' " Romney said of Trump. "We have to have a president who will stand up to cheaters."

Romney talked a lot about Nevada and how Trump created jobs there, but that Nevada led the country in foreclosures, for which he blamed President Obama.

"I spent my life in the private sector — not quite as successful as this guy," Romney said, turning and gesturing toward a gushing Trump. "But successful nonetheless."

The relationship didn't stay quite so glowing.

Trump now agrees that Romney was not as successful as he was. "First of all, he wasn't rich," Trump told Bloomberg, as he took a couple of journalists on a ride in his helicopter at the Iowa State Fair, when asked about a backlash against rich candidates.

Romney, after all, was worth a measly quarter-billion dollars. Nothing compared with the $10 billion The Donald boasts of himself.

Like a real estate deal gone bad, Trump now dismisses Romney. He said in New Hampshire that Romney "choked" in 2012, and that he won't fail like Romney did. "Honestly, honestly, I think he choked, OK?" Trump said.

Romney — who thought about a 2016 bid but decided against it — has returned the favor. He swatted at Trump on Twitter over his comments that Arizona Sen. John McCain, the 2008 Republican presidential nominee, is not a war hero.

He retweeted his wife Ann's comment that she stands with Megyn Kelly — after Trump's comments that Kelly had "blood coming out of her wherever."

He called Trump's comments on Mexican immigrants in the U.S. illegally a "severe error."

It's all kind of a Seinfeldian Bizarro World episode — especially given Trump's words in 2012 about Romney's "self-deportation" plan:

"He had a crazy policy of self-deportation which was maniacal. It sounded as bad as it was, and he lost all of the Latino vote. He lost the Asian vote. He lost everybody who is inspired to come into this country."

Yes. That happened.

"I want to say thank you to Donald Trump for his endorsement," Romney said at the event in February 2012, before closing with: "Thank you, Donald! ... Vote on Saturday. I need every vote I can get."

Romney did win the Nevada Republican caucuses, handily. But he went on to lose Nevada in the general election. In large measure, that was because he was wiped out with Hispanics, who made up almost 1 in 5 voters there — and Obama won them 70 to 25 percent.

Of course, Trump won those Nevada caucuses last month, and several others since.

Copyright 2023 NPR. To see more, visit https://www.npr.org.