It was a beautiful evening overlooking the Hudson River in Ossining, New York, and Zephyr Teachout was standing on a small wooden stage with the sunset behind her. A law professor at Fordham University who first made her name as the online organizer for Howard Dean’s 2004 presidential campaign, she drew laughter and cheers from the crowd of teachers, anti-fracking activists and public employees who had come out to see her. She was telling them a story about a bull.

When she was growing up, she said, her dad got a bull to go along with the chickens and sheep and “occasional pig” on their small farm in Vermont. But the bull didn’t like to stay fenced in, and so in order to get the bull to come back, she would “walk up to him, tickle him on the nose and then turn around and run as fast as I could until I got to the other side of the fence with the bull chasing me and then my dad would close the fence and I would climb back outside.”

She paused for effect.

“So I’m running for governor of the state of New York.”

The audience broke up in laughter, instantly recognizing Teachout’s story as metaphor as much as memoir. The bull, they understood, was meant to be Andrew Cuomo, the powerful incumbent governor—and son of another powerful governor, Mario Cuomo—who is known for his strong-arm tactics and relentless pursuit of his political goals (including a potential run for president in 2016). The child, of course, was meant to be Teachout, the unlikely primary challenger, who manages to outmaneuver her foe using swiftness and wit.

With the September 9 Democratic primary just a few weeks, Teachout has been doing her best to agitate the bull by calling out Cuomo for what many see as his betrayal of basic Democratic principles in favor of stock Republican positions: his attacks on organized labor, his support for charter schools and high-stakes testing, and his penchant for cutting taxes for the rich while cutting services for the poor, to name a few. Embracing a brand of populism that stands in sharp contrast to Cuomo, Teachout has framed these differences as more than a series of policy quibbles. They are, in her formulation, a decisive choice between organizing political principles: between the corruption of private, insider power and the equality that can prevail through true democratic processes.

Until a few weeks ago, these efforts seemed destined for well-meaning obscurity, with Teachout’s candidacy serving, above all, as an opportunity to cast a principled protest vote. With little fundraising muscle or institutional support—the establishment has lined up behind the governor—Teachout and her running mate, Tim Wu, were (and still are) the clear underdogs.

But the last few weeks have shaken up the landscape in ways that shift both the significance and, potentially, the prospects of Teachout’s campaign. As she and Wu have traveled parts of the state, they have managed to tap into some of the profound frustration that people feel with a governor who has come to symbolize the corporate-friendly wing of the Democratic party. But they have also, and perhaps far more significantly, emerged as the anti-corruption crusaders running against a candidate who has been been hit, mid-campaign, by a bruising ethics scandal.

This scandal centers on a commission Cuomo created in 2013 to investigate public corruption and then disbanded months later because its members began to look too closely at some of his friends and donors. Such campaign-season scandals are hardly new, but the fact Teachout is about to publish a book about just this type of political corruption—Corruption in America: From Benjamin Franklin’s Snuff Box to Citizens United—and is considered a leading scholar of corruption has injected her campaign with a powerful sense of relevancy. Of all candidates, few have formulated as robust a critique of today’s politics of corruption as Teachout.

Cuomo is “a symptom of what’s happening in politics and a very disturbing one, when politics loses its representative nature and it loses its leadership,” Teachout told me. “He’s fundamentally, actually, working for private power.”

As Teachout has hammered this message, some big players with national clout have stepped up to support her campaign. On August 14, the Public Employees Federation (PEF), the second-largest public employees union in the state, stunned political observers by endorsing Teachout and Wu, a move that Mike Boland, Teachout’s campaign manager, called “an act of courage and bravery by workers who have a lot at stake.” In the days leading up to that endorsement, the Progressive Change Campaign Committee had given her their blessing, as had Harvard law professor and campaign finance reformer Larry Lessig, who called Teachout “the most important anti-corruption candidate in America today.” And on August 5, as she stood on the stage in Ossining, an endorsement was read from education policy expert and author Diane Ravitch, saying, “I support [Teachout] for two reasons: one is because she has the skills and integrity to be a great governor. The other is because Andrew Cuomo does not.”

During that evening, Teachout certainly had the crowd of about seventy-five, many holding handmade signs in black marker on posterboard, in the palm of her hand. Many of the attendees, like Melanie Rush, a Westchester county resident and a member of the PEF, were already on board with Teachout’s campaign before the event. “One of the worst things in my opinion about Cuomo is the way he so-called negotiated our contract,” she told me. “He offered us a really bad contract taking money away from us, sent out about 3,400 layoff notices, and said if you sign the contract I’ll rescind the layoffs. He didn’t negotiate, he bullied.”

Others, however, like Jake Jacobs, who teaches art in the Bronx, came out to hear other speakers and found themselves swayed by Teachout. “It’s great when people ask questions of the audience and the audience participates, that’s a teacher,” Jacobs said.

To close out her speech, Teachout invoked her own underdog status to heighten the contrast between herself and the governor. “I don’t have his $35 million and I don’t want to be dependent on his donors. I want to be dependent on you. That’s the idea of democracy.”

* * *

Populism has become something of a buzzword in American politics in the last couple of years—a term that has been applied to Massachusetts Senator Elizabeth Warren, New York City mayor Bill de Blasio and just about anyone who has incorporated the term “inequality” into a campaign stump speech. Populism is an old American tradition that dates, as Michael Kazin points out in his book The Populist Persuasion, back before the People’s Party, or Populists, was founded in 1891. The People’s Party, a third party of farmers and laborers, itself rose out of the conviction that the two major parties, the Democrats and Republicans, were controlled by bankers and elites.

If that scenario sounds familiar, it should. As Michael Kink, executive director of the Strong Economy For All coalition, a union-backed group that fights for progressive economic policy in New York State, explained, “There are plenty of pissed-off working people, some of them identify as Democrats, some of them identify as Republicans, but all of them are wildly dissatisfied with the choices that they’re getting in elections and from their government. That’s where the energy in American politics is, whether it’s in the labor and community-driven Working Families Party, whether it’s in the uncontrollable and populist fringes of the Tea Party, the people who are overwhelming the business lobbyists who thought that they controlled the AstroTurf.”

Teachout and Wu have been working hard to channel that energy in New York State. They’re calling for a higher minimum wage, a rollback of Cuomo’s tax cuts for the wealthy, an investment in infrastructure from public transportation to the Internet, and a ban on hydrofracking. On education, they call for a halt to high-stakes testing and for equitable funding in both poor and wealthy school districts; they support returning the right to vote to convicted felons and granting driver’s licenses and tuition assistance for undocumented immigrants. Perhaps most important in this election cycle, when corruption is center stage, they are calling for public financing of elections to cut back the power of wealthy insiders and corporate donors.

There is a third party in New York State that supports most of these principles—the Working Families Party, a labor-backed party that takes advantage of New York’s “fusion” voting laws to endorse progressive Democrats that meet their criteria. It was the Working Families Party that first recruited Teachout, last March, as a possible candidate on their ballot line for November’s general election, against Cuomo. But after Cuomo came to the table and agreed to support some of the WFP’s key proposals (like supporting a Democratic takeover of the State Senate this fall), 58.7 percent of the WFP state committee voted to endorse Cuomo, while 41.3 percent backed Teachout. That means that Cuomo will appear on their ballot line as well as the Democratic party line this fall.

After the WFP about-face, Teachout might easily have bowed out and returned to her life as an activist and professor. But having decided to get into the race, Teachout moved instead to challenge the governor in the Democratic primary. She asked Wu to join her ticket, garnered 45,000 petition signatures to secure her spot on the ballot and successfully defended a legal challenge from Cuomo that attempted to kick her off the ballot.

Wu told The Nation that he thinks their campaign is on the front lines of the soul-searching that both political parties are doing in the face of widespread anger from below. “There’s a certain divide in this country,” he says. “There’s one that is between the Democratic or Republican party, but then there’s another divide which is basically how you feel about how money and wealth are distributed in this country.”

Occupy Wall Street crystallized this divide with its language of the 99 percent versus the 1 percent, and it shook up New York politics in particular. In Albany, the state’s capital, a millionaire’s tax that seemed to be going nowhere and a small minimum wage increase passed in its wake; in New York City, Bill de Blasio sprinted to victory in the 2013 mayoral election by decrying the inequality that had turned New York into “a tale of two cities.”

Now there’s space across the state, said Kink, for political candidates to tap into the energy stirred up by social movements as well as the anger and frustration of New Yorkers who feel like their wages haven’t caught up with their rent or property taxes, while taxes for corporations and the rich have shrunk. Activists might consider running for office as well as protesting in the streets, he said, “because full-throated populism where you don’t pull your punches is really where the action is. I think the public is willing to receive them with open arms and cast a hell of a lot of votes in their favor.”

Teachout, who spent time in the Occupy Wall Street trenches, thinks that the missing piece of the analysis is a term that would have been familiar to the Populists of over a century ago: trust-busting. One of her roles at Occupy, she told The Nation, was educating activists about corporate law and policy. “Re-politicizing anti-trust work, re-politicizing anti-monopoly, that is both the smallest and the biggest challenge in the campaign,” she said. “I will tell you once you get into a room, if you spend more than ten minutes in a room, the biggest excitement is about breaking up big companies.”

Yet there is little language around such a platform, she noted, even among the Democratic party’s biggest so-called populists. That’s why she was drawn to Wu, who coined the term “net neutrality” and has focused his work on telecommunications monopolies, and that’s why her campaign speeches have quite a few echoes of the old People’s Party, references to “twenty-first-century” technology notwithstanding.

Teachout is not a radical at heart. “I’m a down-the-line Democrat,” she said onstage, and has repeated it in interviews. Unlike Howie Hawkins and Brian Jones, the Green Party’s candidates for governor and lieutenant governor, or Kshama Sawant, who won election as a socialist to Seattle’s City Council, Teachout doesn’t boldly trumpet socialist policy. Yet it’s still amazing how radical a simple populist Democrat sounds.

* * *

Many progressives first saw the name Zephyr Teachout (“the name my parents gave me” she says) on a campaign email from Howard Dean’s 2004 presidential campaign. Michael Whitney, today a progressive digital campaigner, worked with Teachout on that campaign, which shaped what we now think of as “online organizing.” On that campaign, he said, he learned from her how to create a community, how to help supporters exercise their own organizing power, how to build something that “wasn’t just about Howard Dean but about the collective ideals and the collective wants and needs of the people who supported him.”

He remembers Teachout getting into a camper that eventually broke down before she made it all the way across the country, traveling from Dean meetup to Dean meetup to talk with supporters. “Her experience has been just talking with people, about what they’re dealing with, showing them how they can be a part of something.”

There’s a lot of that kind of independent hustle about her current campaign as well. I rode the MetroNorth to Ossining with Teachout and two campaign volunteers for the education rally, while she made call after call to the press and was greeted by at least one commuter who recognized her and wished her good luck. She’s undeniably the underdog in this race, with a budget in the hundreds of thousands compared to Cuomo’s millions, and she’s OK with that.

So is her running mate. “I think we’re probably just the first of what will be a long-running series of contests within the Democratic party which really divide on the issue of inequality and private power,” Wu said. “To a degree we’re figuring out whether we’re a party of voters or a party of donors. Which is a delicate question.”

To Whitney, Teachout is doing what she feels she has to do, even without the money, organizers and support that would have come along with a campaign run by the Working Families Party. She may not be building a third party with this run, but she’s gotten some notice outside of New York—the Progressive Change Campaign Committee tells The Nation that 1,500 of its members from all over the country signed up to support or donate to Teachout within twenty-four hours of its endorsement of her campaign. “I think what she can leave behind is the idea that if you do organize, if you do this, you can at least make a dent in the armor of Cuomo, of whatever other establishment candidate is in there,” Whitney said. “If the party infrastructure was behind it it could’ve been much more significant.”

It’s a thankless job, challenging a powerful incumbent. In addition to the big endorsements, on the day I spent with Teachout she was served with a subpoena for records that included her bank accounts, tax returns, rent checks and phone bills as part of the Cuomo campaign’s challenge to her New York residency. They were not able to knock her off the ballot, but fighting the court challenge cost her campaign thousands of dollars. “It’s part of why women don’t run for office—and men don’t run for office but women especially—because, it’s sort of embodied in this subpoena, there is a threat of taking on your dignity. You have to share everything about yourself.”

At the same time, though, she said, “[Cuomo] has everything to lose and I’ve got nothing to lose.” It’s good, she said, to be the underdog, because someone like Cuomo can overplay his hand.

* * *

The best argument for Teachout’s continued run has been the last few weeks of headlines about Cuomo. The Moreland Commission to Investigate Public Corruption, which Cuomo formed in July 2013 and then killed last March, has drawn an investigation from a federal prosecutor into whether the governor illegally attempted to influence the commission’s findings. A blockbuster report from The New York Times has been followed by smaller stories that, among other things, highlight the governor’s outrage at being investigated and opened up a space for a progressive challenger to speak.

Teachout, with her history in studying corruption and her upcoming book, is uniquely positioned to challenge a governor who is known for his ability to draw big donations. She testified as a citizen before the Moreland Commission, she said, “about why we needed to be taking on structural issues and not just enhancing criminal law, why we need to change how campaigns were funded.”

She was actually asked at one point, she said, to submit her CV for consideration to write the commission’s report, though the commission ended up using an inside person. But nevertheless, she has made those same issues a central focus of her campaign—the concentration of private power, its influence over politics, something that she calls onstage “a fundamental democratic betrayal.”

Kink notes that these particular issues of corruption are also issues of economic inequality, and that may be why the Moreland scandal has legs. In just one Moreland Commission investigation, he said, “These billionaires got property tax breaks for their hundred-million-dollar penthouse in the sky condominium, at a time when working class people cannot afford their modest houses in working-class suburbs. When the Moreland Commission investigated the specific billionaire real estate developers who had donated to Governor Cuomo and then got tax breaks in exchange, that’s not just about good government, it’s about economic fairness,” he says. “The two are inextricably linked.”

“The fact that Cuomo could be indicted…is an example of the problem we’re dealing with,” Whitney added.

On the train home from Ossining, Teachout said that long before the Moreland Commission was shut down, she told people that she thought it had taken on a life of its own, that it had become something even the governor couldn’t control. That same feeling is one she has now about the campaign. I asked her what it would say to national political watchers if she managed to win an expected low-turnout primary.

“That you cannot forget the Democrats that are in your state,” she said.