Stephen Lam / Reuters

Bernie Sanders is making a final stand in the place where it all began. A little over a year ago, the Vermont senator started his  U.S. presidential campaign in Washington, D.C. He returned on Thursday to hold one more rally before the nation’s capital hosts the final primary of the Democratic race next week. Sanders has vowed to stick it out until the bitter end, despite the fact that Hillary Clinton has already declared victory. His loyal followers must now confront a painful prospect: If the political revolution Sanders promised ever comes to pass, it won’t happen by electing a 74-year-old Democratic socialist to the White House.

At least some supporters were willing to concede that the Democratic race is essentially over at the rally convened near a run-down stadium in Southeast D.C.  Many wondered aloud, with a mixture of optimism and anxiety, what will happen next. “I’m sad, definitely disappointed. I really wanted to believe Bernie would go all the way. I'm a little bitter, but I'm not going to let that consume me,” Jake Passel, a 32-year-old D.C. resident said. “I think in the long run this will be the start of something that is much bigger than the campaign. But I don't know what will happen in the future, and I'm actually a little worried.”

Loss of any kind is disappointing. Sanders offered a dream of what the country could look like. Now, it may never be reality. Over the course of his campaign, Sanders sketched out an alternate vision for American society. The voices of everyday people would not be drowned out by wealthy elites in the world imagined by the senator. Every man would stand side by side with women in the fight for equal pay. Health care would be a right, not a privilege. Politicians of every party would act decisively to stop the planet from burning up. The campaign was a promise: All of this might actually be achieved. 

Sanders is still making that promise, but he may not be able to for much longer. “Together, we are going to change our national priorities,” the senator told the crowd, a message that was met with loud cheers before he listed off the litany of changes he wants to see. The senator’s agenda could certainly still be put into action, and he will undoubtedly keep fighting for it. But what happens to the political revolution depends, in part, on what the campaign meant to his supporters. Was it mainly about Bernie, or was it about his ideas?

There are limits to what any one person can achieve. The senator is likely to wield far more power and influence when he returns to Congress after the election than he did before. But he has made clear he can’t bring about a political revolution on his own. Adding to that difficulty, it will be harder to sustain enthusiasm once the primary race is over. The American public reviles Congress, an institution consumed by gridlock, where success is often only found in compromise. It’s a place where political dreams go to die. Sanders’s supporters will be sorely disappointed if they expect him to successfully legislate a revolution into being.

In the end, more people sided with Clinton and her vision of the world than with Sanders and his—she won an estimated three million more votes during the primary race. But Sanders proved there is enthusiasm for the agenda he outlined—and far more enthusiasm than many predicted at the start of his campaign. He elevated a critique of unrestrained capitalism above all. If nothing else, his campaign showed that a message of economic fairness wins votes.

There is guaranteed to be at least some spillover effect. Grassroots activism inspired by the campaign is poised to continue. Other candidates may take up the mantle of populist economics. “The awakening has taken place, the genie is out of the bottle, that’s what’s wonderful about it,” Cornel West, a Sanders supporter and academic known for his outspoken criticism of President Obama, told me ahead of the rally. “What form it takes is an open question, but there’s no doubt about it.”

On Thursday, Sanders seemed to be taking part in an unofficial farewell tour. He launched into a recitation of turning points in the history of the United States: the fight to end slavery; the fight for women to vote; the fight for marriage equality. He emphasized that courage, persistence, and effort yield change. “What seemed impossible, what seemed radical, just a few years ago, is now commonplace,” he said.  “What seems radical today will seem mainstream tomorrow if we stand together.” 

The senator did not devote much time to talking about Trump at his rally, but he has promised to help defeat the Republican Party’s presumptive presidential nominee. “Donald Trump would clearly, to my mind and I think the majority of Americans, be a disaster as president of the United States,” Sanders said outside the White House after meeting with the president earlier on Thursday. “Needless to say, I am going to do everything in my power, and I will work as hard as I can, to make sure that Donald Trump does not become president of the United States.”

Some supporters seem ready for that fight. “If Bernie doesn’t get the nomination, we’re going to work to defeat Trump,” Erin Murphy, a 43-year-old D.C. resident said while waiting in line to attend the rally. Yet that may not be a simple or straightforward proposition. Murphy told me she plans to vote for Green Party presidential candidate Jill Stein, not Clinton, if Sanders drops out. “I’ll work to defeat Trump, but I won’t support Hillary,” she said. “It’s a tough tightrope to walk.”

Whatever happens to Sanders’s movement is unlikely to match the energy and enthusiasm that has been built up by the primary campaign. Perhaps the momentum will dissipate or be diverted toward other activism like the climate movement or Black Lives Matter. “There are many different ways that his influence could be exerted beyond the end of this presidential campaign, but it may be scattershot, and less unified,” said Matt Dickinson, a political-science professor at Middlebury College. “It may seem less coherent, and less visible.”

The consequences of Bernie’s presidential bid may not be fully understood for years to come. It’s hard to judge the significance of a political revolution in its midst. In the end, the campaign’s legacy will depend just as much on the actions of the people who supported the senator in his quest for the White House—like those who gathered in the nation’s capital on Thursday night—as it does on the candidate who promised political revolution. 

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