Since the debate lineups were announced, there had been speculation about how Warren and Sanders, who share a broadly common set of policies (though not the same approach to politics), would interact, and about whether the candidates would attack each other or join forces. Warren’s answer was to outflank Sanders without ever needing to attack him head-on.

To that end, she seemed to be focusing on emotion. Early in the night, the candidates engaged in a sometimes fascinating, sometimes infuriating debate about health-care reform. The issue is one on which there are real differences of opinion among the hopefuls, and they engaged in a few substantive exchanges—occasionally overcoming strict timekeeping that felt more and more counterproductive. The result was frustrating, because while the left (Sanders, Warren) and right (Delaney) poles of the debate were clear, the large number of candidates onstage meant it was hard to differentiate among the many nuanced views present. Warren was able to cut through with an anecdote about the progressive activist Ady Barkan, who has ALS.

“This is somebody who has health insurance and is dying,” Warren said. “Every month, he has about $9,000 in medical bills that his insurance company won’t cover. His wife, Rachael, is on the phone for hours and hours and hours begging the insurance company: Please cover what the doctors say he needs. He talks about what it’s like to go online with thousands of other people to beg friends, family, and strangers for money so he can cover his medical expenses.”

Warren is not the only candidate to argue that Democrats should follow their hearts and trust that votes will follow. Pete Buttigieg repurposed one of the more effective lines from his stump speech in the debate.

“It is time to stop worrying about what the Republicans will say,” he said. “If we embrace a far-left agenda, they are gonna say we’re a bunch of crazy socialists. If we embrace a conservative agenda, you know what they’re gonna do? They’re going to say we’re a bunch of crazy socialists. So let’s just stand up for the right policy, go out there, and defend it.”

Buttigieg’s agenda is, in its own way, radical. While Warren’s policy ideas are further left, Buttigieg has proposed an aggressive set of structural reforms to the American system, including packing the Supreme Court and eliminating the Electoral College. “This is a country that once changed its Constitution so you couldn’t drink, and changed it back because we changed our minds, and you’re telling me we can’t reform our democracy in our time?” he quipped.

But it was Warren’s litany of her victories over heavily favored opponents that captured the spotlight tonight. Just after she spoke, Delaney replied in his by-now-familiar role as the dour realist of the field, hectoring the candidates over plans whose math, he says, does not work. “I think Democrats win when we run on real solutions, not empty promises,” Delaney tut-tutted.

Warren’s response was unsparing and evinced genuine exasperation. “I don’t understand why anybody goes to all the trouble of running to be the president of the United States to talk about what we really can’t do and shouldn’t fight for,” she said. “I don’t get it.”

As it turns out, there is something that Democrats—at least those running for president—should fear: incurring Elizabeth Warren’s wrath.