“It’s truly disheartening. I wanted her to succeed in the worst way,” Speier, who has not endorsed in the race, said of Warren. “I think the electorate has not come to the same level of enlightenment that many other countries around the world have: that a woman as president can be in the best interests of our country.”

California Sen. Kamala Harris entered the presidential race as one of the most promising Democratic candidates, only to drop out in December. She told reporters on Capitol Hill Thursday that there is “still a lot of work to be done to make it very clear that women are exceptionally qualified and capable of being the commander-in-chief of the United States of America.”

Warren likely failed for reasons more than gender: She was competing with Sanders for the progressive mantle, while also arguing she could bridge the two wings of the party better than her opponents. She stumbled during her rollout of a Medicare for All plan (though she also faced more pressure than Sanders early on to explain how she'd pay for it.) And she may have played nice for too long with her opponents.

But there's few denying, including the candidate herself, that gender played a key role. Acknowledging the differing expectations female candidates face presents a "trap," Warren said Thursday. When a woman points out she's held to a double standard, she said, she's labeled a "whiner."

Yet avoiding the topic of sexism isn't an option, either. Do that, Warren said, and a “bazillion women think, 'What planet do you live on?'”

Rep. Susan Wild (D-Pa.), who hasn’t endorsed in the primary and said she's at odds with Warren ideologically, nevertheless called Warren's withdrawal “heartbreaking.” Wild immediately thought of her children who supported Warren, including one who worked for the candidate in Iowa.

People always say, “Well, it’s not the right woman,” Wild said. “Well, who’s going to be the right woman? Look at us, we’re as diverse as you can get, we’re all different shapes, sizes, colors. So which one of us is the right woman?”

“That’s what makes me really frustrated. Because nobody ever says, well, 'He’s not the right man,'” she added.

Sen. Mazie Hirono (D-Hawaii) said there's something about a woman running for a top executive post that brings out "strange attitudes" in voters — something she experienced when running for governor in 2002. "They think women are not tough enough, that we can't do the job."

In his book, a Citizen’s Guide to Beating Donald Trump, David Plouffe asserted that “there is more resistance to a woman president then there is to any male minority group, or a male of any sexual orientation.”

“It really is the presidency now that that seems to be a harder ceiling,” Plouffe said in an interview. “Elizabeth Warren was put through a ... crucible of the electability question in a slightly different way than some of the other candidates were.”

Aimee Allison, co-founder of She the People, was on hand when Warren had what some considered a defining moment in her campaign in April. Warren was just starting to gain steam, and the energy was palpable as she received a raucous welcome from hundreds of black and brown women at an event in Houston the advocacy group for women of color in politics hosted.

But the separation between black and Latino female activists and operatives who rallied around Warren’s candidacy, and the actual voters who determined her fate, never bridged.

“My job is to make sure that women of color are encouraged to participate in democracy and yet today is a hard day for me to find the words,” Allison said in an interview. “What privilege is, is that white men get to be the default, they get to be the regular, they get to be the fallback position. And then everybody else ... is the other, is the exception, is the risk.”

Though Allison does not agree with many of Biden’s policies, she said that during her conversations with women of color in states that voted on Super Tuesday, it was clear many simply wanted a reset.

“It’s like we're striving to go to something that resembles some version of normal, even if that normal doesn't get our community's needs fully met,” she said.

Even though six women ran for president and failed, she doesn’t think it will deter other women from running. “It feels like a setback,” Allison said. “But right now, I can imagine a black woman vice president and that's never happened.”

Addisu Demissie, who ran Sen. Cory Booker’s campaign for president, said there’s a “skepticism" that women and candidates of color face but white men do not. Though the skepticism was never overt as Booker — one of two black men to run this cycle — traveled the country, Demissie said, it was always “lurking.”

“There is perceived safety in whiteness and maleness,” said Demissie. “There's a perceived risk in nominating women and people of color that was just too great for the electorate this time. It’s wrong and unfortunate and sad, but politics is about perception.”

Democrats interviewed for this story were careful not to diminish the success of Biden and Sanders, and said they're ready to unite behind the eventual nominee. But those who put their heart behind candidates like Warren, Harris and Booker feel the sting.

Biden and Sanders entered the race with high name ID and it may have been “destiny” that the former vice president and the runner up for the nomination in 2016 would be the last two standing, said Demissie. But “without question the driving force behind most voters decisions and who to vote for in this primary has been electability versus Donald Trump. And that has an inherent bias towards white males that accentuated their already built-in advantages.”

Jess Morales Rocketto, former digital organizing director for Hillary Clinton, said Warren’s fall was “disappointing” and made her feel the way she did after 2016.

But “I don't think that every woman is a referendum on all women,” Morales Rocketto said, and "We're going to lose, and lose, and lose, right up until we win.”

As Warren announced the end of her run Thursday, she recalled the pinky promises she made to young girls across the country when she took photos with families and women who waited in lines that snaked around high school gyms. “I’m running for president because that’s what girls do,” Warren would say.

“I take those pinky promises seriously,” Warren said. And as for the challenges she faced as a female candidate, Warren said, “I promise you this: I will have a lot more to say on that subject later on.”

Sarah Ferris and Alex Thompson contributed to this report.