If Hillary Clinton wins the White House in November, she would be the first female president of the United States.

There would be a few other firsts in the family that night as well: Bill Clinton would be the first man married to a U.S. president. He would also become the first former president to become the first spouse.

Tuesday night, Bill Clinton addresses the Democratic National Convention in Philadelphia to make the case for his wife. It will be his 10th time addressing the DNC.

He has been a popular ex-president and his wife clearly considers him an asset to her campaign — so much so that, in addition to deploying him on the campaign trail, Hillary Clinton happily indulges in speculation about what life would be like for him in a potential second tour at the White House.

And when she does, there's one question that comes up again and again. What exactly would we call him? Hillary Clinton has given it some thought.

"Part of what we'll have to figure out is what do you call the male spouse of a female president? Now it's a little bit more complicated with him because people still call former presidents Mr. President," she said on Jimmy Kimmel Live back in February. "So I have to really work on this... but first dude, first mate, first gentleman, I'm just not sure."

Bill Clinton has even joked about it. When the former president was campaigning for his wife in Iowa back in January, he said he was looking forward to making history in his own way.

"I want to talk about one barrier that has not been broken. I want you to support Hillary for me too. Because I want to break a ceiling. I am tired of the stranglehold that women have had on the job of presidential spouse," Bill Clinton said.

But despite the groundbreaking nature of Bill Clinton's possible new role, Carl Sferrazza Anthony, a historian with the National First Ladies' Library, says the former president has already created a model for himself.

"It's actually going to unfold into a role that's not too dissimilar from the one he's been playing for 16 years as a former president," Anthony said, adding that first ladies have historically avoided partisan issues. "And that's exactly what former presidents do. And that's what Bill Clinton has done," he said.

Through his foundation and through his partnership in charitable efforts with Former President George H. W. Bush, Bill Clinton has been involved in earthquake relief, international aids prevention and small scale agriculture.
Any one of those would make a decent template for a first spouse's focus.
And, says Anthony, even though a male person as first spouse would be unprecedented, the fact that he's been in the White House before could make his new role not so big a change after all.

"Him having been president will make a transition for the country into having the first male presidential spouse much easier and much more familiar," Anthony said, "I don't think anyone will blink when they see Bill Clinton in a tuxedo and Hillary Clinton in an evening gown on the steps of the North Portico welcoming heads of state."

And speaking of formal dinners, Hillary Clinton has been clear: she'll still be picking the place settings:

"With respect to my own husband, I am probably still going to pick the flowers and the china for state dinners and stuff like that, but I will certainly turn to him, as prior presidents have, for special missions for advice," Hillary Clinton said in the ABC News democratic debate in December.

For the most part, Bill Clinton has been an asset on the campaign trail this year, sometimes making a stronger case for Hillary Clinton than she can make for herself.

For her part, Hillary Clinton sees the prospect of Bill Clinton back in the White House as a selling point. While campaigning in Kentucky, though, she might have gotten carried away.

"My husband, who I'm gonna put in charge of revitalizing the economy because, you know, he knows how to do it," Hillary Clinton said. "Especially in places like coal country and inner cities and other parts of our country that have really been left out."

Making Bill Clinton a special emissary to coal country or the inner city is one thing, but former first lady Hillary Clinton learned the hard way that first spouses should never be put solely in charge of anything. When he ran for the first time in 1992, Bill Clinton used to boast that voters would be getting two for the price of one — a declaration that became problematic for the Clintons.

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