PHILADELPHIA — Vermont U.S. Sen. Bernie Sanders told sobbing supporters here last night the time had come to rally around his former rival Hillary Clinton — even as a raucous “Bernie or Bust” revolt threatened to disrupt the former secretary of state’s weeklong coronation.

“Hillary Clinton will make an outstanding president, and I am proud to stand with her here tonight,” Sanders told a prime-time sign-waving audience at the Wells Fargo Center that featured TV close-ups of several of his supporters brushing back tears.

Sanders sought to make the case that a woman he had cast as a tool of Wall Street during the primary understands the problems of working-class families and that between GOP nominee Donald Trump and Clinton, “the choice is not even close.”

Progressive Massachusetts U.S. Sen. Elizabeth Warren also called on Sanders supporters to unite and endorse Clinton in an otherwise tepid speech to delegates.

“I’m with Hillary,” said Warren, adding later: “When we turn on each other, we can’t unite to fight back against a rigged system.”

While the “rigged system” was a reference to Wall Street, it almost certainly reminded Bernie supporters of a fixed Democratic primary depicted in hacked DNC emails.

Warren was booed at one point and some chanted, “We Trusted You!” — a reference to her praising Sanders during the primary before she endorsed Clinton at the end.

Sanders and his former campaign staff pleaded with his backers to rally around Clinton after they booed the mention of her name during a rally he held earlier in the day.

“Our credibility as a movement will be damaged by booing, turning of backs, walking out or other similar displays,” Sanders wrote in an email to his own delegates.

“NO ONE STOLE THIS ELECTION!” Tweeted former Sanders press secretary Symone Sanders. “…We lost. It’s a hard reality for some.”

Sanders supporters — still fuming over the leaked DNC emails — unloaded on party officials in the opening hours of the convention. Boos rang out at the first mention of Clinton’s name, followed by chants of “Bernie! Bernie!” And there were reports that Sanders delegates from California shouted the Republican ?refrain, “Lock Her Up!”

Democrats even turned to comedy to turn the tide at one point, bringing out Minnesota U.S. Sen. Al Franken, the former “Saturday Night Live” writer and Clinton supporter, and Sarah Silverman, a comedian and Bernie backer.

But when that, too, resulted in “Bernie” chants, Silverman admonished the crowd. “To the Bernie or Bust people — you’re being ridiculous,” she said.

Maine state Rep. Diane Russell — a Sanders supporter — told delegates they should take comfort in rule changes that diminish the impact of superdelegates in the primaries, which gave Clinton a huge edge throughout the primaries.

“I want to be clear we did not win this by selling out,” said Russell. “We won this by standing up. We won this by standing together.”

Simply gaveling the gathering to order turned into a prolonged soap opera. DNC Chairwoman Debbie Wasserman Schultz was forced to resign after she was heckled at a Florida delegate breakfast. But in a sign of just how disorganized the convention had become, her replacement, Baltimore Mayor Stephanie Rawlings-Blake, opened the session, but forgot to slam down the gavel and had to scurry back to finish the task.

Democrats desperately need to come together soon as the first day of their convention saw Trump benefit from a post-convention bounce. Several national polls showed him surging into the lead over Clinton by as many as 5 points.

Bob McGovern contributed to this report.