In June, first-time candidate for elected office Alexandria Ocasio-Cortez did something almost unimaginable when she defeated 10-term incumbent Congressman Joe Crowley in the Democratic primary in New York’s 14th Congressional District—by nearly 15 percentage points, no less. Endorsed by progressive groups as well as the New York City chapter of the Democratic Socialists of America, Ocasio-Cortez mostly stayed under the radar until after the election, when she came a political celebrity overnight. Because her candidacy wasn’t perceived as a legitimate threat, she managed to avoid political attacks and harsh media scrutiny during her campaign—her opponent didn’t even bother to show up for their first scheduled debate.

Three months later, Julia Salazar—dubbed “the next AOC” by many pundits—did something even more astonishing. Despite an arduous trial contesting her status as a New York State resident, followed by weeks of negative press calling into question key elements of her biography, and reports of a bizarre scandal involving accusations of theft and fraud against her by the ex-wife of her childhood neighbor Keith Hernandez, she ousted New York State Senator Martin Dilan by 17 points, a margin of victory even higher than Ocasio-Cortez’s. How was that possible?

There were two keys to this victory, according to Salazar’s campaign manager and NYC-DSA member Tascha Van Auken. (Full disclosure: I am a member of NYC-DSA.) The first was having a candidate willing to run openly and unabashedly on a democratic-socialist policy platform. Salazar spoke to the material needs of the district’s residents, advocating for popular policies like universal rent control and universal health care without hesitation or apology.

The other key was the massive field operation that NYC-DSA built. Salazar was the third candidate endorsed in Brooklyn by NYC-DSA since the organization’s membership surged in 2016. The first two were City Council candidates Khader El-Yateem and Jabari Brisport. While neither candidate won, Van Auken says that the lessons learned and the internal capacity built during those campaigns was critical to the success of the Salazar campaign.

“The experience of the 2017 campaigns prepared us to build a structure that could organize and wield the power of volunteers and grassroots energy,” she says. By the time the Salazar endorsement was passed at the NYC-DSA convention in May, NYC-DSA members were ready to hit the ground running. In all, 1,883 volunteers signed up for 4,663 canvassing shifts. Over the course of the campaign, supporters knocked on over 120,000 doors and had conversations with over 10,000 voters. That was a huge increase from the El-Yateem and Brisport campaigns, during which NYC-DSA knocked on about 20,000 doors for each.

Van Auken emphasizes that the volunteers were not just DSA members, and that coalition partners like Make the Road and New York Communities for Change were vital to increasing the scale of the field operation. While DSA was folded into every aspect of the Salazar campaign, there was a deliberate attempt to welcome volunteers not affiliated with any organization.

Another lesson learned in both the El-Yateem and Brisport campaigns was that the strongest and most persuasive talking points were about housing. That informed the strategy for Salazar’s canvas scripts. Van Auken says that “especially in North Brooklyn, the epicenter of gentrification,” affordable housing was an extremely effective issue for getting voters’ attention.

The scale of the campaign’s ground game came as a surprise even to Van Auken, who compared the level of enthusiasm to the Obama campaign in Pennsylvania in 2008, which she worked on: “We regularly had weekend shifts with 100 people coming to canvas for Julia, and 20 to 30 people showing up on weeknights to volunteer.” With such an enormous operation, it’s not that surprising that voter turnout in the district rose by over 250 percent from 2014.

Salazar’s opponent was not so fortunate. While he was one of the top recipients of real-estate donations in the State Senate, his constituents were apparently less supportive. One NYC-DSA member reported that on Election Day, a paid Dilan canvasser told Salazar supporters that he voted for her over his employer because politicians “need to fuckin’ listen and you guys listen.”

Salazar and the platform she ran on inspired people to believe that a better world is possible. People who had never been involved in politics before showed up to a campaign office for the first time because they saw a growing, grassroots movement, and a candidate who promised to be a voice for them.

That’s why reports of dishonesty on the part of Salazar came as such a shock. There have been countless articles detailing the various scandals that battered the campaign in the final weeks. The merits of the accusations have been contested, but the fact is that Salazar said things that simply were not true on many occasions during the campaign. Versions of her biography contained claims that were found to be inaccurate. Two organizations rescinded their endorsements when it was discovered that she had falsely claimed to have graduated from Columbia University. It’s not clear what accounts for these inaccuracies. Many have chalked it up to inexperience and a complicated life story, and have blamed the extreme scrutiny the media seemed to place on her, combined with the opposition she faced from moneyed interests threatened by her candidacy.

Whatever the cause, Van Auken says that, while the attacks took a personal toll on the candidate and campaign staff, volunteers and voters seemed mostly unfazed. It’s understandable that her supporters would feel defensive. Salazar was the target of one of the most cynical and cruel media attacks I’ve ever seen when she was outed by The Daily Caller as one of over a dozen women who have accused David Keyes, the spokesperson to foreign media for Israel’s prime minister, of sexual assault. The apparent attempt at a vicious smear against Salazar backfired, but the pain it caused was real, and her supporters rallied around her.

It’s precisely that sort of visceral support for a candidate and the movement they represent that inspires people to devote months of their lives to help them get elected. “You see people working so hard your mind is blown,” Van Auken told me. “They are there every day because they care really deeply about meaningful change.” People like this are sometimes referred to as “true believers.” They truly believe in the people and causes they are fighting for. True believers are the backbone of any grassroots movement, and that’s why a breach of trust is so dangerous. The hours of labor that won this campaign were donated by people who had faith in the candidate they were fighting for. In people-powered campaigns, that faith is a precious resource. Anything that calls a candidate’s integrity into question is a real threat to a movement that purports to counter the status quo of the untrustworthy politicians of the establishment.

One NYC-DSA member I spoke to, who canvassed for the campaign in the final week, described his interpretation of the news this way: “I had a mixed reaction to the stories. There was obviously a concerted smear job by The Daily Caller that I found disgusting (and ultimately that’s what got me to canvas). But then there was other stuff that made me more than a little annoyed.… Why couldn’t she keep her story straight? Now her ability to articulate a socialist vision and lend credibility to other races is compromised.”

Van Auken says that the next step for NYC-DSA’s electoral operation is to learn from this experience and come up with strategies to prevent another August surprise. “We have a much more evolved idea of how much money, energy and time our opposition will spend when we run candidates opposed to monied interests. Overall, we need a heightened awareness of how much a candidate is going to be attacked,” she says. “This was a horrible experience for us all, and there is a lot we can do to better prepare and better protect campaigns and candidates in the future. Last year we learned how to run an effective field operation. This year we’ll learn new lessons from this experience.”

The good news is that the organization has already demonstrated that its platform is extremely popular and it has the organizational capacity to turn people out to vote. DSA’s success doesn’t live or die by any individual candidate. And if you can get nearly 2,000 people to volunteer for a state-senate primary campaign, just about anything is possible.

Meanwhile, the Democratic establishment learned something too. The old, machine-style political tactics didn’t work. The lawsuit Dilan filed to challenge Salazar’s residency status was typical of this approach, says Renée Paradis, who represented Salazar in the trial: “In Brooklyn, if you have a way to try to kick someone off the ballot, you do.” Paradis says the attorney for Dilan went after Salazar on the stand “above and beyond what was appropriate and necessary to win the case.” The court found in favor of Salazar. Dilan appealed the decision and lost again.

Every attempt to thwart the Salazar campaign failed. Nothing could make up for the fact that the incumbent was completely incapable of matching the grassroots support on the ground. DSA has to work on candidate vetting and communications strategy, both of which the organization seems capable of doing. The political establishment faces a much steeper task, which is figuring out how to convince an increasingly activated electorate to support the unpopular policies that have led to massive rent increases, displacement, and growing inequality. My money is on the socialists.