The enemies at an Elizabeth Warren rally are usually the same: big banks, giant corporations, and corrupt Washington politicians. But at Warren’s crowded campaign stop in Brooklyn on Tuesday, supporters pointed fingers at another one: misogyny.

In between cheers of “two cents!” (a reference to Warren’s proposed wealth tax) and “CFPB!” (the regulatory agency she spearheaded in 2007,) supporters talked about their belief that sexism was weighing down their candidate.

While Warren’s campaign surged over the summer, her popularity has faded in recent weeks, leaving her in third place in New Hampshire polls and fourth in Iowa (behind the all-male trío of Joe Biden, Bernie Sanders, and Pete Buttigieg.) Her fundraising also dipped to just $21.2 million this quarter—far behind Sanders’ $34.5 million take.

At Tuesday’s rally, a number of voters said the problem was that their candidate had flown too close to the sun—at least as far as men were concerned.

“When she started getting a lot of closer scrutiny, I think a lot of people got freaked out about whether she could win in a general election,” said longtime supporter Alexis Roblan, 35. “And I know that a lot of people I know in my life had a moment of, 'Oh my god, can a woman actually win?’”

Susan O’Connor, 68, was more direct: “I think it’s because the men are going after her because she’s too smart.”

“I apologize on behalf of my gender,” the man behind her said, looking sheepish.

At the event, Warren attempted to revive her drooping campaign with a show of support from former rival Julian Castro. The former HUD secretary dropped out of the Democratic race last week and quickly endorsed Warren’s campaign, calling her “the candidate who can unite the Democratic Party.” He is reportedly working as a campaign surrogate, campaigning with her at events in Iowa and likely in Nevada and Texas.

In some ways, the pairing makes sense: Without Castro in the running, Warren’s is now the only Democratic campaign to have more female donors than male. And while Castro did not mention gender explicitly in his remarks, he did praise Warren for being a “fighter”—a label other men in the race have said makes her sound too uncompromising and angry.

“I had the opportunity to see all of the candidates, to get to know many of the candidates, to understand them,” he said. “This is what I understand about Elizabeth Warren: she is a fighter for everyday Americans.”

Castro and Warren entered the event together, stopping in the rain to address an estimated 1,500 supporters who could not make it inside. Afterward, Castro stuck around for Warren’s signature selfie line, which lasted more than three hours.

The more than 3,000 fans who made it inside the Kings theater were handed signs sporting both politicians’ names: “I’m a Warren Democrat,” and “We Heart Julian.” O’Connor, however, wasn’t carrying a sign at all. She said she wasn’t completely sold on Warren yet, and had attended the event partially out of spite.

“I’ve given Elizabeth money, I like her, and the men in my life keep telling me she’s not eligible,” she said. “It gets me really angry.”

Others were angry with what they called a “double standard” against Warren. The candidate has taken heat in the last few months for her Medicare for All proposal and, more recently, for appearing to back down on the issue when it proved unpopular. But to Karen Bonuck, a professor at the Albert Einstein College of Medicine, the criticism smacked of sexism.

“I love that she sort of hedged a bit and said, ‘Let’s see how it goes,’” she said. “But I think she needs to call out the double standard that she’s the only one who's given a detailed plan.”

"Bernie Sanders has not given that level of detail, but no one’s on his tail,” she added. “That’s absolute misogyny.”

The discussion question of a double standard also extended to Twitter this week, when CNN commentator Chris Cillizza criticized Warren for changing her language around Iranian general Qassem Soleimani.

“Warren and Buttigieg have added to their initial statements as they've taken press questions and done TV interviews," Washington Post reporter Dave Weigel tweeted in response. “For whatever reason, Buttigieg isn't getting the same ‘he used different words, can you trust him?’ coverage.”

Sexism will undoubtedly have an effect on Warren’s campaign. While women leaders have been shown to be more effective for their constituents, an Ipsos/Daily Beast poll conducted this summer found only 33 percent of Democratic voters thought their neighbors would be comfortable with a female president. And in a recent New York Times poll, 40 percent of voters said they agreed that most of the women running for president just weren't that likable.

Amy Klobuchar called out sexism in the presidential race in November, saying female candidates were “held to a different standard” than their male competitors. Even Biden acknowledged as much at a campaign stop last week, saying Hillary Clinton had faced “unfair” gender-based attacks in 2016, and adding, “That’s not going to happen to me.” (A campaign official later clarified that Biden was not making the case that women were less electable.)

But aside from a few practiced remarks about pregnancy discrimination and equal pay on Tuesday, Warren stayed away from the issue of gender inequity during her appearance in Brooklyn. Instead, she took the opportunity to punch up at some of the men running against her, on one of her signature issues.

“Some billionaires have taken issues with the wealth tax,” she said, in an obvious jab at former New York City Mayor Michael Bloomberg. “Others have been moved to run for president.”

“I guess he thought it was cheaper than paying a two-cent wealth tax,” she added, to cheers.