Editor’s Note: Julian Zelizer is a professor of history and public affairs at Princeton University and a New America fellow. He is the author of “Jimmy Carter” and “The Fierce Urgency of Now: Lyndon Johnson, Congress, and the Battle for the Great Society.” The opinions expressed in this commentary are his.

Story highlights

Julian Zelizer: Clinton and Sanders played out epic battle in Brooklyn, with each coming out of distinct, longstanding Democratic tradition

He says Sanders needed to show he understood policy; Clinton needed to show heart, not just mind. She succeeded better than he

Brooklyn, New York CNN  — 

Brooklyn was raucous Thursday night. The two Democratic presidential candidates went head to head for their New York debate in the Duggal Greenhouse in Brooklyn – and the atmosphere was, to say the least, tense.

It was impossible to miss the animosity that exits between the supporters of Hillary Clinton and Bernie Sanders: they have become deeply engaged in this epic battle between two very different voices within the Democratic Party, each of whom comes out of a very different, longstanding tradition.

Sanders is the warrior of the left who taps into the spirit of Ted Kennedy, Eugene McCarthy and other politicians who have argued that change starts from the bottom up and leaders need to be adamant about principle. And Clinton is the champion of Washington-based pragmatic liberalism who – like Lyndon Johnson, Hubert Humphrey, Jimmy Carter, Bill Clinton and to a certain extent Barack Obama – believes that Democrats need to make adjustments in order to survive within a very conservative political world.

Democratic presidential candidates Sen. Bernie Sanders, I-Vt., right, and Hillary Clinton speak during the CNN Democratic Presidential Primary Debate at the Brooklyn Navy Yard on Thursday, April 14, 2016 in New York. (AP Photo/Seth Wenig)
Hillary Clinton defends her role in Libya
01:40 - Source: CNN

Tonight each campaign had a very different challenge as they arrived in Brooklyn ready to defend their approach. Sanders needed to assure voters that he has a strong grasp of the details of public policy and he needed to prove that he is still committed to the kind of campaign he promised when he once told the public he didn’t care about Hillary Clinton’s “damn emails.”

For Clinton, the challenge was the same that she has faced from the very start of the campaign: the need to inspire voters and win over their hearts, not just their minds. Beyond the high decibel attacks each would end up making on the other, these were the challenges that were on the table when the candidates entered the room in Brooklyn.

So who won? Who walks out of Brooklyn in the best position to win the delegates on Tuesday’s New York primary?

Sanders certainly had many good moments. He scored points, particularly on money and politics and by raising questions about Clinton’s record on foreign policy: her support of the Iraq war and – according to him – her failure to anticipate the aftermath of the U.S.-backed military operation to oust Moammar Ghadaffi.

Clinton pressed about releasing speech transcripts
02:49 - Source: CNN

But Clinton did very well in three areas. First she turned the “special interest issue” against him, with the interest being guns. He struggled to explain his gun control voting record and didn’t quite answer a question about whether he would apologize to Sandy Hook victims, as one family member has called for, for “putting the gun lobby above our families.”

Second, she brought home a key point several times, namely that it is easy to diagnose a problem, but harder to do something about it. She did so – for example, on the issue of fracking, where Sanders criticized her “incrementalism” on energy policy – while emphasizing a sense of what compromises did. This is an area of vulnerability for Sanders.

Finally, during a discussion of the Supreme Court, she brought up her commitment and determination to fight for women’s issues, blasting the fact that so few questions had been asked during the primary campaigns about women’s reproductive rights.

NEW YORK, NY - APRIL 14:  Democratic Presidential candidates Hillary Clinton and Sen. Bernie Sanders (D-VT) debate during the CNN Democratic Presidential Primary Debate at the Duggal Greenhouse in the Brooklyn Navy Yard on April 14, 2016 in New York City. The candidates are debating ahead of the New York primary to be held April 19.  (Photo by Justin Sullivan/Getty Images)
Bernie Sanders on Clinton: 'I do question her judgment'
02:44 - Source: CNN

Both candidates apparently came into the room Thursday night ready to throw down, and at certain points, the interrupting and loud talking over each other recalled a few of the earlier GOP debates more than the relatively civil exchanges Clinton and Sanders have had until recently.

But overall, Clinton did slightly better in terms of her performance. She didn’t have many gaffes, and she didn’t allow Sanders to make any serious dents in her campaign.

At the same time, she put onto the agenda – often over the very vociferous shouts from the Sanders supporters in the room – the basic message that she wants undecided voters to be thinking about when they make their decision on Tuesday. She can walk away from Brooklyn secure in this.

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