Actress Rosario Dawson addressed delegates and supporters of Vermont Sen. Bernie Sanders’s presidential campaign at a rally at the Democratic National Convention in Philadelphia on Monday, where she warned that if Republican Donald Trump defeats Hillary Clinton in November, it won’t be because of Sanders’s steadfast supporters.

“He’s got 1,900-plus delegates. We’re here,” Dawson said at the rally. “We’re just supposed to fall in line and go with what the party wants and we went, ‘No, no, no, no, no.’ Because it’s not about Bernie, and we’ve been saying that the whole time, but I don’t think they believed it because so many other people are running because of ego.”

The 37-year-old Sin City star, a longtime supporter of Sanders’s presidential run, went on to praise a more progressive Democratic Party platform before turning her attention to Hillary Clinton, whom she called “not a leader,” but rather a “follower.”

The actress’ mention of Clinton’s name drew loud jeers from the crowd.

“She follows public opinion on things, so if we stay strong on universal healthcare, if we stay strong on the fight for fifteen, if we stay strong on all of these things… our revolution is dependent on your time, your energy, your blood, sweat and tears, your persistence, your commitment, your dynamism, you and us, making we together.”

Dawson also called on Sanders supporters to ensure Clinton be “held accountable” for promises she has made.

“This is vehemently true if Trump becomes president, because he’s the one saying no to the TPP [Trans-Pacific Partnership] deal,” Dawson went on. “And we’re saying the same thing. And if the Democratic platform doesn’t accept it and then Trump becomes president because of it, that’s not our fault or lack of trying. So stay the course.”

Dawson has been a vocal critic of both Clinton and the Democratic National Committee. In March, the actress told Sanders supporters at a rally that the DNC was boosting the Clinton campaign to prevent Sanders from receiving the party’s presidential nomination, a claim that has been given new life in the wake of the leak of thousands of DNC emails last week.

Dawson also took on Clinton at a rally in New York in April for suggesting that Sanders did not care about women’s issues. “Shame on you, Hillary,” the actress said then.

Dawson is just one of several pro-Sanders celebrities in Philadelphia for the Democratic National Convention this week.

On Sunday, actors and Sanders supporters Susan Sarandon, Danny Glover and Shailene Woodley led a rally for more than 1,000 people at a park to bring attention to climate change issues.

Follow Daniel Nussbaum on Twitter: @dznussbaum