President Obama hosts Mitt Romney for a private lunch at the White House today, little more than three weeks after their bitter election fight ended.
Yes, Obama did say at a post-election news conference that he hoped to "get ideas with him and see if there's some ways we can potentially work together."
But is cooperation with a former opponent really possible?
It's not without precedent, says Scott Farris, author of Almost President: The Men Who Lost the Race but Changed the Nation.
After Wendell Willkie lost the 1940 presidential election to Franklin D. Roosevelt, Farris notes, he became the president's unlikely ally. Willkie spoke on behalf of Roosevelt's controversial Lend-Lease Act to aid American allies in World War II and helped secure passage of the military draft, which Roosevelt supported.
Then there are Stephen Douglas and Abraham Lincoln — once bitter rivals from opposing political parties who became close friends and allies after Lincoln's election.
And yet, says Dan Balz, Washington Post political correspondent and co-author of The Battle for America, 2008, post-election cooperation across party lines seems to be the exception rather than the rule. Former political opponents, he says, often seem able to do little more than carry on civilly.
And even that is not always guaranteed.
"Barry Goldwater in '64 knew he lost in a landslide. But he went to bed without giving a concession" to Lyndon B. Johnson, says Farris. "There can be some lingering bitterness that's hard to get over."
Days after Republican John McCain delivered a gracious 2008 concession speech in which he acknowledged the historic nature of Obama's win, the two competitors had a meeting in Chicago. They agreed to work together on the nation's problems, including "solving our financial crisis, creating a new energy economy, and protecting our nation's security."
But Obama and McCain's relationship quickly soured, and the two have hardly worked together. McCain has become a sharp critic of the administration (including, most recently, the administration's handling of the Benghazi, Libya, attacks). At a health care town hall meeting in 2010, after McCain accused Obama of failing to deliver on a change he had promised, Obama pointedly reminded McCain: "We're not campaigning anymore. The election is over."
Balz, who followed Obama and McCain's relationship from its beginnings in the Senate, says: "Their relationship was never that great. During the campaign it was not particularly good. What happened after the election was it just carried on from what it had been."
The same may apply to Obama and Romney.
"They went through a very tough campaign and it was clear that they didn't often seem to like each other very well," says Balz.
But cooperation could happen, Farris says. Romney is not exactly a dogmatic Republican and does not have deep ties to party activists that might inhibit him from crossing over the line.
Further, Romney may have something to gain from working directly with the Obama administration. Unlike McCain, who returned to his Senate seat after his failed bid, Romney now holds no political office and may be looking for a new way to make his voice heard in government.
"It's hard to imagine they'd be working on much together," Balz says. "But strange things happen."