With the New Hampshire primaries just days away, Democrats Hillary Clinton and Bernie Sanders met on a debate stage in Durham on Thursday. In their first one-on-one matchup, the duo seemed determined to illustrate Archilochus’s classic binary between the fox, who knows many things, and the hedgehog, who knows one important thing. Sanders knows that what the country needs—the only thing it needs—is a political and economic revolution. Clinton knows the country needs progressive policies on a range of matters and a pragmatic, realistic strategy to implement them.

That divide was clear from their opening statements, with Sanders immediately jumping to his familiar mantra about a rigged economy and a corrupt campaign-finance scheme. Clinton’s answer was not so laser focused, discussing a general need for the nation to “live up to our values in the 21st century,” and checking off not just the economy, but racism, sexism, and more. This split is not new, of course, but with Martin O’Malley off the stage and out of the race, and the Democratic contest tighter than ever, the division has never been so clear. It led to an unusually interesting debate, with the two candidates frequently addressing each other directly and delving into detail.

At times, it was clear why Sanders’s hedgehog approach has been so popular with many Democrats—the ones who nearly delivered him an upset win in the Iowa caucuses, and the ones in New Hampshire who favor him by some 20 points in polls. That was especially true as they squabbled over who is a true progressive and as Clinton tried to defend her highly remunerative speeches to Goldman Sachs. But at other times, it seemed more like a limitation. Quizzed on foreign policy, Sanders seemed at sea about events overseas.

The first segment of the debate focused largely on labels, picking up on an argument that has raged over the last few days over who is a progressive and who is not. Sanders has pointed out, and did again on Thursday, that Clinton identified herself as a “moderate” last fall; he said that one can be a moderate or a progressive, but not both. “What we have got to do is wage a political revolution.” Clinton rejected that as simplistic, presenting herself as “a progressive who gets thing done” and suggesting Sanders would not. The two also fielded questions about Sanders’s recent registration as a Democrat and which of them is an outsider.

There are two ways to see the fight over progressivism. On one level, it’s a rather frivolous piece of identity politics. Who cares what they call themselves? But for Sanders, it’s a way to show that Clinton says different things to different audiences. Whatever else you care to say about Sanders, he hasn’t changed his story for decades. The conversation also forces Clinton into silly places, such as insisting that she’s not part of the establishment. Does any American really believe that? But Clinton, playing aggressively, got in a couple good licks at Sanders, arguing that his definition of a progressive would rule out Barack Obama, Joe Biden, and even Paul Wellstone, and adding “I don't think it was progressive to vote against the Brady Bill five times.”

More clearly substantive was a fight over the role of Wall Street in American politics. Clinton botched a question Wednesday about a series of highly remunerative speeches she delivered to Goldman Sachs, and she again struggled with it Thursday. The former secretary of state noted that she gave many speeches to various organizations. But of course, that’s beside the point: Sanders’s objection isn’t to Clinton making money, but to Clinton taking payments from big banks. He described Wall Street as based on “fraud” Thursday and noted the lack of prosecutions of financiers after the 2008 crash. Clinton still hasn’t crafted a good answer to criticism of her ties to finance—a pretty good sign that there isn’t a good answer to be had. (Later, moderator Chuck Todd asked Clinton if she would release transcripts of all the speeches she gave; her answer, “I’ll look into it,” was neither inspiring nor convincing.)

The Wall Street discussion produced the single most-heated moment of the debate, when Clinton lashed out at Sanders. She notes that he accuses politicians of being influenced by money, but never specifically names her. "I think it’s time to end the very artful smear that you and your campaign have been carrying out,” Clinton said. The line came in the midst of a loud back-and-forth between the candidates, and elicited both cheers and boos. She also said she had never changed a vote because of a campaign contribution—but that’s not the way systemic corruption works. Sanders, the hedgehog, gets that; Clinton, the fox, sees so many shades of gray that the picture gets fuzzy.

The debate next turned to foreign policy. On many specifics, both candidates agree. For example, both think the U.S. should be working against ISIS, and both oppose sending ground troops to do it. Sanders stressed that the United States should avoid foreign entanglements. Clinton reeled off a list of policy variables with elan. Sanders brought up his vote against the war in Iraq, but asked about the relative menace of North Korea, Russia, and Iran, he quickly proved out of his depth, meandering and making questionable assertions. (Multiple dictators in North Korea?) Clinton can speak with much deeper knowledge on foreign policy, but the fact remains that she erred in voting for the war in Iraq, as Sanders was happy to remind viewers. “A vote in 2002 is not a plan to defeat ISIS,” she said Thursday—surely true, but voters might reasonably question her judgment about ISIS given her record. In one sharp exchange, Clinton delivered a detailed critique of Sanders’s suggestion that the U.S normalize relations with Iran; Sanders accused her of making the same mistake she’d made in 2008, when she called Obama naïve for wanting to negotiate with Iran about nuclear weapons.

Both candidates delivered strong performances, and both drove into a couple of potholes. Given what a non-factor Martin O’Malley had been in the previous debates, it’s surprising how different this debate felt. But Clinton had deftly played herself against Sanders and O’Malley as a pair time and again, and removing O’Malley deprived her of the chance to do that. Sanders’s Manichaean perspective on campaign finance and the economy is simple and appeals to many Americans, and it makes it hard for Clinton to defend her record. The heavy emphasis on just a few issues for most of the debate plays into Sanders’s hedgehog strengths. Moreover, because Sanders has the momentum, Clinton was forced to attack him. How voters respond to that remains to be seen, while her continued insistence that Sanders would dismantle Obamacare still doesn’t make sense.

Sanders entered with momentum and did nothing to lose it, meaning he probably gains more from the debate—but it’s hard to make a case that Clinton lost the debate. The big winner from the night might be the American people: After months of overcrowded debates, the chance to see just two serious presidential candidates engage each other was a valuable and refreshing change of pace.

—David Graham