When the returns started coming in from local elections in Denver on Tuesday, it quickly appeared as if more people had turned out to vote for the effective decriminalization of psilocybin, the psychoactive ingredient in magic mushrooms, than for the incumbent mayor. The podcaster, comedian, and UFC commentator Joe Rogan had issued a last-minute plug on Twitter and Instagram. Lance Cayko, communications director for the Libertarian Party of Colorado, and one of the biggest endorsers of the initiative, had long ago expressed his support. The decision was imminent—and at 7 PM Mountain Time, Kevin Matthews, campaign manager for what is formally known as the Denver Psilocybin Initiative, was at a watch party with almost 200 others. The results, however, didn't look promising for them. All day long, the national press had reported how the early tallies showed the measure narrowly failing.

Still, "yes" votes kept trickling in. At 1 AM, Matthews recalled, the initiative had gained more than two percentage points. He decided to clean up and head home, holding out hope, however tentative: There were still 40,000 votes left to be counted.

"We kept the faith," Matthews told VICE on Wednesday night. "We just kept believing in it."

He was onto something. By Wednesday evening, the nail-biter finally came to a conclusion. And it was a good one. Initiative 301, which seeks to decriminalize possessing and using mushrooms for personal use for those 21 and older by making it the lowest local law enforcement priority and blocking spending on penalties, had narrowly passed. According to the latest tally from the city's official site, it had 50.6 percent of the vote with 89,320 votes in favor and 87,341 against.

Now, Matthews said, he had to call both potential mayors, whose fates reside in a runoff. He had plans to let them know he looked forward to pushing this movement along. The first task: putting together a review panel "to assess and report on the effects of the ordinance."

The mayor's office has until December 2019 to sort it out with him, but he is eager to push the timeline up. He's preparing to work with the Justice Department—magic mushrooms remain very much illegal under state and federal law—as well as city officials, the police, and the sheriff's office, and provide them with whatever resources they need.

"I'll be lobbying at the Denver city and county buildings," he said on Wednesday night. "Probably starting tomorrow."

A former West Point cadet who was honorably discharged, Matthews had dealt with major depression, especially after he saw the trajectory of his life shift when the army was no longer a viable option for him. After a particularly beneficial experience with mushrooms, he began a grassroots campaign to get psilocybin decriminalized in the city of Denver.

His measure, according to the Denver Post, was "likely put over the top" in the final stretches "by young voters, who tend to cast their ballots closer to or on Election Day, even though all registered voters receive their ballots in the mail about three weeks" prior.

But whatever happened, Matthews was never just blowing smoke. Psilocybin has begun to creep into the public consciousness as a serious substance. Last October, the US Food and Drug Administration (FDA) granted psychedelic psilocybin therapy "breakthrough therapy” status after a slew of academic institutions found promising results for its treatment of psychological conditions ranging from depression to PTSD, the larger body of research supported by business leaders with mainstream credibility. The success in Denver may have been a barely successful test, a triumph that nearly missed stumbling over the finish line at the last second, but a win is a win: Matthews accomplished what nobody else in history has before, and he has set a decriminalization precedent for the rest of the United States.

"We've been studying psilocybin for its potential therapeutic applications, and it appears to be very considerable, if utilized wisely and with proper caution," said Charles Grob, a professor of psychiatry and biobehavioral sciences at UCLA whose research has focused on psilocybin and cancer patients facing existential anxiety at the end of their lives. "What's so interesting about the psilocybin treatment model is that the patient population that might optimally respond are those who do not respond well to conventional treatments,” he added, clarifying that he was referring to people with substance abuse problems and obsessive compulsive disorder.

Getting this on the ballot, then, was just the first step— passing decriminalization was the second. Matthews, for his part, was just thrilled to be creating this kind of dialogue. He has set the stage for similar ballot initiatives in 2020, like in Oregon, where the secretary of state approved the language for a ballot initiative last December, and in California, where activists are still in the process of massaging that very legal language.

"For all intents and purposes, it was four months that resulted in an approximately 50–50 split on an issue that has never been put to voters before," said Noah Potter, a New York–based lawyer and drug reform expert, who founded and runs the New Amsterdam Psychedelic Law blog, is the general manager for the NYC Cannabis Parade, and served as the chair for the New York Bar Association’s Committee on Drugs and the Law. Matthews had tapped Potter to help him craft the language for the initiative, after he initially failed to get it approved by the Denver Board of Elections.

"[All this] will encourage organizers, and help them recruit and raise money," Potter later said. "Psychedelic reform is now legitimate and credible. It will shape the background for all media coverage for those initiatives. And it could create the opportunity to engage in deeper, more comprehensive, and more holistic coverage of all drug issues, since this electoral action came from out of nowhere, and is way off the grid."

This was the primary takeaway that Matthews and Potter emphasized: the momentum that was built around the cause. They had been hopeful, too, because there was never really any particularly vocal or organized opposition to the campaign—other than that of the incumbent mayor, Michael Hannock, and Beth McCann, Denver's district attorney and top cop, whose spokesperson wrote to me in an email that while she would not back the campaign because the city is currently "in the early stage of marijuana's legalization, and because [it] could make Denver a magnet for those who want to use psilocybin," she did back "the provision of the initiative that forms a committee to study the effects."

"There may not have been that much opposition because psilocybin doesn't play a major role in the criminal justice system," said Jag Davies, director of communications for the pro-reform Drug Policy Alliance. (According to the Washington Post, "Denver police arrested 50 people in each of the past three years for sale or possession of mushrooms, and prosecutors pursued only 11 of those cases.")

Nonetheless, Matthews has established the way into the future—and the rest of the country will be looking to him, his city, and the members of the Denver Psilocybin Initiative to implement safety parameters and inform the public on benefits and best procedures. But, more importantly, it'll be looking to him for how to energize a group of people around an idea that has been stigmatized for decades. Early polling from the Oregon initiative showed promising returns in January, with 47 percent saying that they'd vote "yes" or were "leaning yes," and 46 "no" or "leaning no"—Denver's results could very well boost it over the edge.

"What we accomplished here in Denver represents a clear signal to the rest of the country that Americans are ready for a broader conversation around psilocybin," Matthews said. "And no person deserves to be criminalized for possession and use. Now we have the opportunity to continue that conversation, and to educate people. We're just getting started."

Sign up for our newsletter to get the best of VICE delivered to your inbox daily.