That’s because political strategists, academics and other observers have long seen a pattern play out when female candidates put their husbands front and center: “People start to question, who’s really in charge?” said Kelly Dittmar, a Rutgers University professor who studies women in American politics.

“For men, there’s more complicated terrain in just how active they want to be in order to preserve the independent view of their wife,” Dittmar continued.

That was a dynamic former Michigan Gov. Jennifer Granholm’s husband, Dan Mulhern, battled when she became the state’s first female chief executive in 2003. In an interview, Mulhern said he and Granholm dealt with “sexist undertones and implicit bias,” including “people who thought I was somehow calling the shots, which is the furthest thing from the truth.”

“That’s the liability, potentially undermining your female spouse who’s a female executive,” said Mulhern. “We’re looking for a picture of power, and we haven’t had a lot of examples of men in blue suits be the supporter, rather than at center stage.”

A primary in the year 2020 is a relatively safe space to begin pushing past these questions, according to Democratic campaign operatives. And the campaigns still have to focus on managing public impressions of the candidates before they can worry too much about their husbands.

“It’s something I think about, but not the number one thing,” said one senior campaign official. “Before we get to the gendered perceptions of the potential first man, we have to tackle the gendered perceptions of the first female president.”

But Democrats are already wondering how general election voters — or President Donald Trump, with his uninhibited record of prodding societal hot buttons — will react next year.

“In the general election, it’s a different story,” said another senior campaign official, who added: “That’s when how and what way we roll out [the husband] will matter more, when it will be a more complicated question as to how to do it.”

Voters have not often seen men in the “supportive role” in campaigns, said Jen Palmieri, a former communications director for Hillary Clinton and Barack Obama’s presidential campaigns. And when they have, it has largely been for legislative roles, not executive ones: Only 3 percent of governors in American history have been women, according to an analysis by Dittmar.

“It’s a challenge to puzzle through how voters want to see it, what kind of role they want to see that man in,” Palmieri said. “There’s no playbook for it.”

Some of the other 2020 spouses can literally open the playbook from their husbands’ past campaigns. Former second lady Jill Biden is a regular presence in the early states for former Vice President Joe Biden’s campaign, while Jane Sanders continues to play a critical strategic role for Bernie Sanders, as she did in 2016.