Bernie Sanders onstage in Philadelphia. Photograph by Philip Montgomery for The New Yorker

When Bernie Sanders walked out to address the Democratic National Convention, on Monday night, at Philadelphia’s Wells Fargo Center, which normally serves as home to the N.B.A.’s hapless 76ers, he was fully aware that many of his supporters were ready for a fight. Earlier in the day, when the Vermont senator had appeared for a pre-D.N.C. event at the Pennsylvania Convention Center, he had been roundly booed after suggesting that it was time for the Party to unite around Hillary Clinton. He had then texted an appeal to some of his supporters: “I ask you as a personal courtesy to me not to engage in any kind of protest on the floor. It's of utmost importance you explain this to your delegations.”

As the D.N.C. got started, in the mid-afternoon, the pastor who read the opening prayer, the Reverend Dr. Hale, was also interrupted with boos, as well as some cheers, when she mentioned Clinton’s name. No organized protest materialized, but from there, the proceedings degenerated into something of a shouting match, with Sanders supporters, particularly some from the California delegation, trying to drown out the speakers with shouts like “Bernie! Bernie! Bernie!” and “We want Bernie!” Marcia Fudge, the Ohio congresswoman who, on short notice, replaced Debbie Wasserman Schultz as the chair of the Convention, was moved to remark, “We are all Democrats, and we need to act like it.”

The heckling continued nonetheless. Even Senator Elizabeth Warren, who spoke after Michelle Obama’s much-lauded address, and who has long been a favorite of progressives, wasn’t spared. As Warren appealed to the crowd to work hard for a Clinton victory in November, there were angry chants of “We trusted you! We trusted you!” One woman shouted, “You sold your birthright for a bowl of porridge.”

Sanders may have feared that he would receive similar treatment, for there was little doubt about what he would say. Shortly before his speech, his wife, Jane, spoke with NBC News, invoking Sanders’s endorsement of Clinton two weeks earlier at Portsmouth High School. “I think you heard him, in New Hampshire, give a full-throated endorsement. He'll continue to do that today, ” she said. Pressed on what, if anything, she and her husband could do to rein in their supporters, she said, “We can't tell people what to do. We don't want to tell people what to do. We want to engage them.”

In Philadelphia, the stage was much larger than it had been in Portsmouth, but the address Sanders delivered was, in substance and language, very similar. As he tried to start talking, he was interrupted repeatedly with cheers and shouts of “Bernie! Bernie! Bernie!” He isn’t known as a sentimental man, but the din was so loud and passionate it appeared to move him close to tears.

When the crowd finally quieted down, he began, as he had in Portsmouth, by saluting the volunteers and supporters who had turned his insurgent campaign into a nationwide phenomenon. Then, addressing his delegates—all eighteen hundred and forty-six of them—he said, “I look forward to your votes during the roll call tomorrow night.” That generated more shouts of “We love you, Bernie!” From a box in the rear of the hall, Bill Clinton looked on silently.

Sanders passed the crisis point, and his supporters hadn’t turned on him en masse. *Photograph by Philip Montgomery for The New Yorker * Photograph by Philip Montgomery for The New Yorker

Then Sanders changed tack. Noting that nobody was more disappointed than he was by the result of the primary, he started to build a case for taking a larger view of things. “Election days come and go, but the struggle of the people to create a government which represents all of us and not just the one per cent ... that struggle continues,” Sanders said. “This election is about—and must be about—the needs of the American people and the kind of future we create for our children and our grandchildren.” Reminding the crowd of the economic mess that George W. Bush and the Republicans bequeathed eight years ago, he praised President Obama “for pulling us out of that terrible recession,” and said, “This election is about which candidate understands the real problems facing this country and has offered real solutions—not just bombast, not just fearmongering, not just name-calling and divisiveness.”

Until this point, Sanders had mentioned Donald Trump only in passing, but it was clear where he was headed. “We need leadership in this country which will improve the lives of working families, the children, the elderly, the sick, and the poor,” he said. “We need leadership which brings our people together and makes us stronger, not leadership which insults Latinos and Mexicans, insults Muslims and women, African-Americans, and veterans, and seeks to divide us up. By these measures, any objective observer will conclude that, based on her ideas and her leadership, Hillary Clinton must become the next President of the United States.”

If Sanders was to be drowned out, which was never very likely, this was the moment when it would have happened. Although he got only partway through the next sentence in his prepared remarks (“The choice is not even close”), he was not overtaken by the crowd. There were some boos and catcalls around the hall—quite a few of them. Some Sanders supporters were so overcome with emotion that they cried. But there were also cheers from Clinton supporters, and shouts of “Hillary! Hillary! Hillary!” The room was still divided; that much was clear. Yet it was also evident that Sanders had passed the crisis point, and that his supporters hadn’t turned on him en masse.

So far, the argument he had been making for Clinton was the same one a number of prominent Republicans (if not Ted Cruz) had made for Donald Trump in Cleveland last week: the alternative is much worse. But, unlike Paul Ryan and Scott Walker, Sanders didn’t leave it at that. He also made the case for Clinton directly. “Hillary Clinton understands that if someone in this country works forty hours a week, that person should not be living in poverty,” he said. A bit later, he added, “Hillary Clinton will nominate Justices to the Supreme Court who are prepared to overturn Citizens United and end the movement toward oligarchy that we are seeing in this country.” And: “Hillary Clinton understands that we have to invest in education and jobs for our young people, not more jails or incarceration.”

In one sense, these incantations were merely an acknowledgment from Sanders that there is more that unites than divides Democrats of the center- and far-left. But they were also examples of Sanders keeping his part of a negotiated agreement between his campaign and the Clinton campaign, which in return for his endorsement produced, as he put it, “by far the most progressive platform in the history of the Democratic Party.” Sanders mentioned specifically its calls for the passage of “a twenty-first-century Glass-Steagall Act” and its opposition to “job-killing trade agreements like the T.P.P.” Then he said, “Our job now is to see that strong Democratic platform implemented by a Democratic-controlled Senate, a Democratic House, and a Hillary Clinton Presidency—and I am going to do all that I can to make that happen.”

By this stage, on social media, some Clinton supporters who had been complaining about the first part of the speech, which hadn’t mentioned the candidate much, were coming around and praising Sanders. Bill Clinton also appeared to be warming to him. When Sanders recalled Hillary as “a great First Lady who broke precedent,” the former President smiled and applauded. Sanders was now wrapping up. “I served with her in the United States Senate and know her as a fierce advocate for the rights of children, for women, and for the disabled,” he went on, gesturing with his right hand. “Hillary Clinton will make an outstanding President, and I am proud to stand with her tonight.”

With that, the man who many people believe won the war for the soul of the Democratic Party while losing the battle for the Presidential nomination, said, “Thank you all very much,” raised his right arm in the air, and, pausing barely at all to take in the crowd reaction, walked off the stage.