If Trump chooses Romney, someone who repeatedly denounced his candidacy, some say it may represent an effort to bridge the divide with the establishment he spurned during the election season.
Here is everything you need to know about Romney:
Name: Willard Mitt Romney
Age: 69 (born March 12, 1947)
Family: Romney comes from a political family. His father, George W. Romney, was a governor of Michigan. Mitt Romney is married to Ann Romney and has five sons.
What he does now: Romney is retired from politics and business.
What he used to do: Romney was the GOP presidential nominee in 2012 and lost to President Barack Obama. That was his second time running for the GOP nomination; he lost to Sen. John McCain in 2008. From 2003 to 2007, he was the governor of Massachusetts. He helmed the 2002 Olympics in Salt Lake City. In 1985 he co-founded the private equity firm Bain Capital.
Education: Stanford (attended 1965 to 1966), Brigham Young University (graduated valedictorian in 1971), Harvard (earned a dual degree in law and business in 1975)
What you may not know: Between attending Stanford and Brigham Young, Romney did a 30-month tour as a Mormon missionary in France.
International experience: Romney has never been a diplomat. Although he did business throughout the world while with Bain Capital, he is now retired, which would likely help him steer clear of potential conflicts of interest.
Compared with Trump and the reputation he built as a strict isolationist during the presidential campaign, Romney — simply by virtue of his traditional Republican values and the importance he placed on the NATO alliance during his 2012 campaign, for example — could be seen as an more of an internationalist or at least someone who could balance the Trump administration in that direction.
He is viewed as having a steady temperament for the world stage, which would be reassuring to other world leaders and members of the GOP establishment.
He and Trump, however, could differ on Russia. An ABC News investigation found Trump has numerous connections to Russian interests in the U.S. and abroad. Trump told Vladimir Putin he's looking forward to having a "strong and enduring relationship with Russia." But in a 2012 presidential debate, Romney called Russia America's biggest geopolitical foe.
The men could find common ground against Iran — both oppose the nuclear deal — and China, where both have a firm belief in confronting currency manipulation and enforcing stricter standards for trade.
Fraught relationship with Trump
Romney and Trump have a history that predates this election. They went to football games together at Gillette Stadium in Massachusetts, and Trump endorsed Romney for president at a big Las Vegas event.
However, this campaign season, Romney was one of Trump's major critics and was especially critical of Trump in a nationally televised speech on March 3.
"Here's what I know: Donald Trump is a phony, a fraud," Romney said in that speech. "His promises are as worthless as a degree from Trump University. He's playing members of the American public for suckers: He gets a free ride to the White House, and all we get is a lousy hat."
In that speech, Romney opined that Trump's "foreign policies would make America and the world less safe."
These comments about Trump are leading some in his inner circle to publicly oppose picking Romney. "We don't even know if he voted for Donald Trump," his former campaign manager, Kellyanne Conway, said on "Meet the Press" this weekend. Newt Gingrich and Gov. Mike Huckabee have said Romney should not be picked as secretary of state and point to that speech as a red flag, questioning his loyalty to the president-elect.
Here are some other highlights from that speech:
Romney called Trump a "con man" and "a fake."
"Think of Donald Trump's personal qualities — the bullying, the greed, the showing off, the misogyny, the absurd third-grade theatrics," Romney said. "We have long referred to him as 'the Donald.' He is the only person in America to whom we have added an article before his name. It wasn't because he had attributes we admired."
"His domestic policies would lead to recession," Romney said. "His foreign policies would make America and the world less safe. He has neither the temperament nor the judgment to be president. And his personal qualities would mean that America would cease to be a shining city on a hill."
Romney also attacked Trump for not releasing his tax returns, which he still has not done. "I predict that despite his promise to do so, first made over a year ago, he will never ever release his tax returns," Romney said. "Never. Not the returns under audit, not even the returns that are no longer being audited. He has too much to hide ... If I'm right, you will have all the proof you need to know that Donald Trump is a phony."
Finally, Romney called out Trump for this 9/11 controversy: "He said he saw thousands of Muslims in New Jersey celebrating 9/11. Wrong. He saw no such thing. He imagined it. His is not the temperament of a stable, thoughtful leader. His imagination must not be married to real power," Romney said.
Trump has volleyed back. He has repeatedly called Romney a "choke artist" and said that he "choked like a dog," that he was a "disaster as a candidate" and that they were not friends.