This past Saturday, I was lucky enough to have witnessed one of the most moving political victories of working people in recent memory.

Over 100 service workers—and a seemingly equal number of reporters—packed into the Grand Ballroom of the Bellagio Hotel and Casino, the largest of seven Democratic primary caucuses on the Las Vegas strip. As the chair called the caucus to order at noon, it was anybody’s guess how the vote would go.

My expectations were low. Sanders had strong polling numbers across Nevada, and I was optimistic about the political influence of immigrant children upon their Culinary parents. (As one middle school student attending the caucus with his father explained to us, “My dad always told me I needed to get a scholarship, but with Bernie’s plan everyone would get a scholarship.”) But after a weeks-long push by union leaders against Medicare for All, those of us in the room who were Sanders campaign organizers would have been happy if our candidate made it past the first round.

Shortly after noon, caucus participants were asked to rise from their chairs and vote with their feet. The vast majority promptly marched directly to Sanders’s side of the room. Surprised by their strength, Bernie’s supporters erupted in cheers and more than one of us broke down in tears.

It would be hard to overstate the political importance of Saturday’s win, which was replicated across the seven Las Vegas strip caucuses. A workforce made up predominantly of women of color enthusiastically gave their votes to a candidate who mainstream media pundits have repeatedly told them is backed only by white guys. Though one should never underestimate the perfidy of the corporate punditry, it’s possible that these strip workers, together with Nevada’s broader multiracial working class, may have finally put the “Bernie Bro” myth out of its misery.

No less importantly, these housekeepers, blackjack dealers, servers, and taxi drivers may have single-handedly saved the movement for single-payer health care. The Vegas strip caucuses were nothing short of a national referendum, broadcast live across the country, on whether union workers would support or oppose Medicare for All. Though they did not formally endorse any candidate, Culinary Union Local 226 union officials had been arguing to members for weeks that Sanders’s proposal would eliminate their deeply loved insurance plan, which they had won through decades of strikes and struggle.

Given the indisputable power and progressive credentials of the Culinary union, there is no doubt that the media and Democratic establishment would have immediately declared Medicare for All to be dead on arrival had Sanders lost the strip. But rank-and-file Culinary workers obliterated that argument Saturday afternoon.

During her one-minute speech following the first round vote, Monica Smith—an in-room dining order taker at the Bellagio and member of the union since 1987—explained why so many Culinary members support eliminating private health insurance plans: “I love my union and my health care plan, but Bernie doesn’t want to restrict our great health care coverage. He wants to expand it to everyone—and to improve our own health care by eliminating all co-pays. Bernie will make it so that we can maintain great health care even if we lose our jobs—and he’ll ensure that our children will have great health care once they become adults. Don’t our children deserve the right to health care? Don’t all of our neighbors and workers outside of Culinary deserve great health care their whole lives too?”

After Sanders’s decisive showing on the Vegas strip and across Nevada, it will be increasingly difficult for unions across the country to remain on the fence about his signature health care proposal—or his campaign to win the White House.

Saturday had a euphoric feel similar to the victory of the 2018 wildcat teachers strike in West Virginia. After decades of defeats, it felt like history, finally, was moving on the side of working people. And, again, rank-and-file workers saved the day—and transformed themselves in the process.

Though a team of Bernie volunteers played an important role in boosting turnout for the strip caucus, the big story of the day was that hundreds of workers stepped up as leaders. At Bellagio, a steady stream of workers volunteered on the day of the caucus for tasks ranging from speaking to the media to passing out Bernie buttons, to convincing their coworkers to vote Bernie. Across the strip, Ethiopian taxi drivers spread the word about the caucus over the Viber text messaging app and turned out in big numbers. And at the Wynn casino, a Latina culinary worker whom none of the Bernie team had ever met before volunteered to make the realignment speech and brought down the house, moving five of the six nonviable Elizabeth Warren delegates to join up with the Bernie caucus.

Like a successful strike, winning elections for working-class candidates can be a profoundly transformative experience. Hundreds of workers on the strip dared to vote for Bernie on Saturday—and they were justifiably proud of what they achieved. As caucus participants streamed out of the ballroom to return back to work, group hugs, high-fives, and beaming faces were the norm. People were somehow standing taller.

As I stood at the ballroom exit, shaking the hands of Sanders supporters, I couldn’t help but start imagining how it might feel to win the nomination and the presidency. If winning one Las Vegas strip caucus in a presidential primary could have such a transformative impact upon working people, it’s hard to even imagine the wave of working-class confidence that would be generated if Bernie Sanders wins the White House. Which is a good thing. Because for a President Sanders to be able to implement his ambitious agenda, he’ll need every bit of the militant enthusiasm and organized activism of millions of workers like those who shocked the establishment this Saturday at the Bellagio.