Bernie Sanders empathized with his disappointed supporters but told them firmly that Hillary Clinton must win in November.

“Any objective observer will conclude that — based on her ideas and her leadership — Hillary Clinton must become the next president of the United States,” Sanders told Democratic National Convention delegates, some of them in tears during his speech.

The senator from Vermont sought to unite Democrats on the opening night of their convention, even as primary season divides were exacerbated by a leak of emails showing party leaders sided against his campaign. At various moments, shouts of “Bernie! Bernie!” rang out during speeches.

There was an orchestrated effort by some of the party’s most popular figures to heal the divides and bring Sanders supporters to Clinton’s side.

First lady Michelle Obama delivered an emphatic endorsement of Clinton, declaring “I’m with her” and taking a sharp swipe at Republican nominee Donald Trump, sparking a euphoric reception.

Liberal heroine Sen. Elizabeth Warren slammed Trump as a man who skipped on his debts and cheated other people, while saying Clinton was one of the “smartest, toughest, most tenacious people on this planet.”

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