Vermont Sen. Bernie Sanders was faced with intense backlash from his own camp as he addressed the delegates at the Democratic convention on Monday night.
Sanders struggled to begin his speech over the raucous crowd chanting his name, which took several minutes to die down, but made a point to thank his many supporters and donors across the country.
"Let me thank the 13 million Americans who voted for the political revolution, giving us the 1,846 pledged delegates here tonight –- 46 percent of the total," he said to wild cheers from the audience.
"I understand that many people here in this convention hall and around the country are disappointed about the final results of the nominating process. I think it's fair to say that no one is more disappointed than I am," he said, acknowledging the frustrations of his backers. "But to all of our supporters –- here and around the country -– I hope you take enormous pride in the historical accomplishments we have achieved."
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The crowd erupted again in pro-Bernie cheers when the candidate first mentioned his former rival, Hillary Clinton.
"Hillary Clinton must become the next president of the United States," he said, before pausing for nearly a minute to wait for the outbursts to subside.
"Sad to watch Bernie Sanders abandon his revolution," Trump tweeted. "We welcome all voters who want to fix our rigged system and bring back our jobs."
Sanders then proceeded to make the case for Clinton over Trump, comparing the two on a number of issues including health care, economic issues, criminal justice and climate change. Those remarks all united the delegates in anti-Trump boos.
He also made a point to acknowledge the points on which he and Clinton disagree, while championing the progressive planks that the two negotiated into the Democratic Party's platform.
But his mention of the Trans-Pacific Partnership deal incited another round of anti-TPP chants.
"Hillary Clinton will make an outstanding president and I am proud to stand with her here tonight," he said as his final line. Some began chanting "he's with us," as the senator left the stage.