Hollywood director Rob Reiner is attempting to win over diehard Bernie Sanders supporters — “Bernie Bros” — by encouraging them to line up behind Joe Biden, promising that Biden will bring about the “biggest landslide” election in U.S. history.

On Monday, Rob Reiner tweeted a call for Democrat unity shortly after Bernie Sanders endorsed his former rival Joe Biden. “If Sen. Sanders’ supporters do the same, Decency, Humanity, Science and Justice will defeat ignorance, Racism, Corruption and Incompetence by the biggest landslide in U.S. History,” Reiner wrote.

Bernie Sanders has given his full throated support to Joe Biden. If Sen. Sanders’ supporters do the same, Decency, Humanity, Science and Justice will defeat Ignorance, Racism, Corruption and Incompetence by the biggest landslide in US History. — Rob Reiner (@robreiner) April 13, 2020

Reiner has been voicing his support for Biden since March, at one point writing that Democrats need to put their differences aside and coalesce behind Biden. The director of The Princess Bride, This is Spinal Tap, and A Few Good Men said in April that he believes Biden possesses the “best chance” to defeat President Trump in the next election.

“I think that if he [Biden] becomes president, on day one, America will be brought back to where it belongs in the world,” said Reiner.

Other celebrities to urge Democrats to unify behind Biden include Alyssa Milano, Barbra Streisand, and Rosie O’Donnell.

But many Bernie Bros are refusing to obediently fall in line. On Sunday, the Democratic Socialists of America tweeted that it won’t endorse Biden. Many have cited the current sexual assault allegation against Biden brought by former staffer Tara Reade, who has accused the politician of using his fingers to penetrate her against her will.

We are not endorsing @JoeBiden. — DSA 🌹 (@DemSocialists) April 12, 2020

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