Sources close to MSNBC host Joe Scarborough think he is seriously considering the prospect of leaving morning television to run for president in 2016.

Last week, Scarborough was all smiles — even letting out a laugh — on “Morning Joe” when Weekly Standard editor Bill Kristol suggested on the air that Scarborough could represent the “Jon Huntsman lane” in a 2016 GOP primary. (RELATED: Kristol to Scarborough: You’ll run in 2016 to ‘fill the Jon Huntsman lane’)

But behind the scenes, those who know Scarborough are not laughing.

It’s widely believed at MSNBC — including among network brass — that Scarborough is actively mulling a presidential bid, sources said.

Meanwhile, some of Scarborough’s guests are beginning to talk him up as a possible candidate. Mark McKinnon — the former adviser to George W. Bush and John McCain who co-founded the group No Labels and appears on Morning Joe regularly — said he has talked about the prospect of a White House campaign with Scarborough “ever since we first met years ago, but always in the abstract.”

“On paper, he’s a great candidate,” McKinnon told The Daily Caller. “He has the kind of confidence, ideas and media savvy required to make it on the big stage. And he’d be a lot of fun to watch because he wouldn’t be afraid to mix it up with anybody on any topic. I think it would be highly entertaining and good for the party.”

Added McKinnon: “I think Joe looks at the potential field and thinks, ‘I could compete.’ And I think there are potential donors and supporters who think the same thing.”

Another Scarborough friend — a Republican who has appeared as a guest on Morning Joe many times — said the notion of a 2016 campaign is no joke: “I definitely wouldn’t fall in the laughing category.”

“I think it’s a very wide open field,” the friend told TheDC by phone. “He’s an articulate spokesperson for conservatives. No doubt about it.”

Here is the thinking behind a Scarborough bid:

The field is wide open.

Republicans won’t nominate a senator. They want a D.C. outsider.

Scarborough would perform well in debates, which mattered in the 2012 contest.

Scarborough, through his recent book, has offered a blueprint for reform for the GOP.

There are just as many hurdles for Scarborough that would likely be turnoffs in a Republican nominating contest: His show represents the thinking of the Washington and New York political elite. He works for a liberal news network. He’s been divorced twice. He resigned from Congress.

“Now, realistically, his MSNBC association and some of his positions could kill him in the crib (though, a lot of people would be surprised to discover he is more conservative than they think),” McKinnon acknowledged. “And professionally and economically, it could be just this side of crazy. But no one ever accused him of playing things safe.

“I’d say he’s got a pretty good itch and one of these days, some year, he’s gonna scratch it,” McKinnon added.

Scarborough did not return an email seeking comment for this story. But in an interview with TheDC in November, the MSNBC host said he was open to running for office again.

“I suspect in the future — if that happens again — and I feel the calling to do it, I’ll do it with the one hesitation — that I got a 10-year-old girl who has said I can’t do it until she’s out of high school,” Scarborough said.

“I don’t know if I’m going to make it that long,” he added. “But I don’t think I’m going to be jumping in anytime soon.”

Scarborough acknowledged that he wrote his recent book, “The Right Path: From Ike to Reagan, How Republicans Once Mastered Politics–and Can Again,” with the 2016 presidential election in mind.

“The reason I wrote the book and the reason I’m going around the country talking about these issues is because 2016 is going to be an extraordinarily important year,” Scarborough said. “We can’t lose another election.”

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