Washington (CNN) Hillary Clinton blasts Sen. Bernie Sanders in a new documentary, saying "nobody likes him" and declining in an interview with The Hollywood Reporter to say whether she would endorse and campaign for him if he's the Democratic 2020 nominee.

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"He was in Congress for years. He had one senator support him. Nobody likes him, nobody wants to work with him, he got nothing done," Clinton says in the film, according to The Hollywood Reporter. "He was a career politician. It's all just baloney and I feel so bad that people got sucked into it."

The comments in the documentary are aimed directly at his core campaign appeal -- that he's a political outsider pitching revolutionary change.

The new round of lacerating attacks come less than two weeks before the Iowa caucuses, which Clinton narrowly won in 2016 and where Sanders is locked in a tight four-way race this year. They also have the potential to reignite a divisive, four-year-old fight that has never fully faded from Democrats' minds. More recently, and in comments since her loss to President Donald Trump, Clinton has blamed Sanders for damaging her campaign.

In response to Clinton's remarks, Sanders said in a statement that his focus was President Donald Trump's impeachment trial.

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