Via Ben Smith, I see that John McCain is hosting a fundraiser for Mitt Romney in Phoenix next week. Back in January of 2008, this would have seemed more unlikely than Obama picking Hillary as his Secretary of State. But as Sasha Issenberg reported out a few weeks ago for this Boston Globe Magazine article on Romney, Mitt did a pretty masterful job of getting on McCain's good side once McCain secured the nomination:

Romney returned to his office the following week [after dropping out of the race] in a T-shirt and jeans, ready to travel to his California home. From there, Romney’s staff informed McCain’s, he would be willing to travel to Arizona for a formal endorsement ceremony. But McCain’s camp volunteered their candidate, campaigning that day in Rhode Island, for an immediate photo op in Boston. Romney wavered about doing it so quickly -- he held a ticket for a middle seat on a JetBlue flight later that day and hesitated about paying the cancellation fee -- but was flattered that McCain would show deference and come to him. Hours later, after postponing his flight and changing into a suit, Romney met with McCain privately for 15 minutes and asked what he could do. McCain made a standard request: He entreated Romney to campaign for him and other Republican candidates. Then the two walked out in front of an American flag and made it official.

It was an early indication that Romney’s long-term strategy would be undiverted by the grudges and pique that often endure among rivals. When McCain found himself in a similar scenario against George W. Bush eight years earlier, he had prolonged the end of his flailing campaign, projected a visible discomfort when he finally endorsed, and participated in a “shadow convention” that drew attention away from Bush’s nomination. Romney decided to be a good soldier.

“That we just put down to him being smart,” says Mark Salter, a McCain adviser who was among Romney’s most vehement detractors during the primaries. “He got out and then graciously said, ‘Put me to work.’ And I don’t think he turned down anything we asked him to do.”

Of course, this whole approach only seems to reenforce the most potent line of attack against Romney--namely, that he's a robotic fraud. Wouldn't it be more beneficial to Romney at this point if he demonstrated that he could nurse a grudge?