WASHINGTON — As Cory Booker nears a decision on whether to run for president, the New Jersey senator has a lot to consider:

The demands on his time and family. How to distinguish himself in what might be a historically crowded field. How to balance the demands of his party’s liberal base and moderate swing voters. Every potential candidate thinking about running will have to grapple with those issues.

But there’s one factor that might be unique among the two dozen or so Democrats eyeing a 2020 run: He’s single.

America hasn’t elected an unmarried president since 1884 -- and only two have ever taken office without having been married first. If he runs, Booker, 49, would try to be the third.

While that might not be a top concern for Booker -- or many voters -- as he mulls his future over the holidays, a Booker presidential run would test the country’s evolving expectations of the presidency.

America is accustomed to not just a chief executive who leads the government, but a First Family that rounds out the ceremonial and symbolic aspects of the job. Spouses and their children can become national figures in their own rights, and often soften a candidate’s image.

Booker, who has thrived on personal notoriety and sharing bits of himself on social media, says all he can do is be himself.

“Clearly the norms of family relationships have been changed dramatically as you’ve seen people across this country being elected to offices with all different kinds of family situations, including the president who has had three spouses,” he said in an interview Thursday in his Capitol Hill office. “So I think a lot of that conventional thought on that doesn’t apply.”

Indeed, the 2017 and 2018 elections saw an increasingly diverse mix of candidates elected to public office, from one of the first openly transgender women elected to a statehouse to the first openly gay man elected governor.

The presidency and a national election, however, would be another test altogether. The office holds a unique place in the public eye, and candidates' personal traits and quirks become part of the national conversation. In past campaigns we learned that Bill Clinton loved McDonald’s and wore briefs, that President Trump likes his steak well done, with ketchup, and that Barack Obama had a ruthless side on the basketball court.

Members of the First Family often become quasi-celebrities. America watched the children of Clinton, George W. Bush, and Obama grow during their fathers’ White House tenures. Their college decisions made headlines. Trump’s children are among his most prominent surrogates, with daughter Ivanka and son-in-law Jared Kushner holding high-level positions in the White House.

Booker’s relatives, including his mother and brother, have been prominent presences in his past campaigns, offering some of the family touch that other candidates might get from bringing their spouses and kids up on stage. The impact on their lives is likely to be a major consideration as Booker weighs a run.

Like any Democrat hoping to challenge Trump, he will likely face an incumbent president who revels in personal attacks.

Booker is undeterred. “I’m going to run on who I am, whether that’s running for reelection [to the Senate] or running for president,” he said. “I’ve always trusted the voters enough to evaluate me on the content of my character, quality of my ideas, and my ability to do the job.”

(Booker, for his part, is a vegan and a former football player at Stanford University. At the time of his Thursday interview with the Inquirer he was 42 hours into a 48-hour fast he undertook with an aide who was trying to lose weight. He apologized for being tired and hungry. And Booker himself appeared significantly slimmer than when he joined the Senate in 2013, perhaps another indication of his presidential preparation.)

Bill Palatucci, a close friend and counselor to former New Jersey Gov. Chris Christie, who ran for president in 2016, said the personal commitment demanded by a national campaign is much harder to weigh than the political issues at play.

“What’s my support? What’s my message? Who has committed if I run? That’s the easy stuff,” Palatucci said. “The more difficult set of issues for anyone to evaluate are the personal factors.”

In the last presidential campaign, Sen. Lindsey Graham (R., S.C.), who is also single, faced questions about campaigning as a bachelor (he suggested a rotating cast of family and friends could be first lady). In past political campaigns Booker’s opponents have tried to use his single status to question his sexuality.

“I’m heterosexual,” Booker said in an interview Thursday when asked about insinuations that he is gay. He has addressed the same point before — and is practiced at moving on to the bigger picture: ”Every candidate should run on their authentic self, tell their truth, and more importantly, or mostly importantly, talk about their vision for the country."

As to whether he actually runs, Booker expects to consider the decision over Congress' holiday break. He said he plans to speak with family, friends, and political advisers as he spends time in New Jersey and Las Vegas, where his mother lives.

“I have a pause during the holidays which is going to be a really great time to meet with family and friends and really start to put some focus on whether to run for president or not,” Booker said.

He would not elaborate on what internal questions remain unanswered, or when he might decide, other than to say that it’s “an incredibly serious challenge to take on.”

Much of the political world, at least, believes Booker’s recent trips to Iowa (in October) and New Hampshire (last weekend) are clear signs that the senator is all-but-certain to announce a presidential run. Booker has also begun speaking to potential campaign aides.

A decision from Booker is widely expected in January as the jockeying in an unusually crowded field begins. In the interview, Booker wouldn’t put a time frame on an announcement. But after his politically weighted travels he laid out a theme that could serve as the pillar of a national run.

Asked what messages he has heard from voters, he said: “The thing that encourages me the most is the thing that I think this country needs, is sort of a revival of civic grace. This idea that we need to bring this country together, this idea that we have common pain but we need to be reunited in a sense of common purpose again.”

This story has been updated to provide additional context about Booker’s comments on his sexuality.