WASHINGTON (1010 WINS) -- Sen. Bernie Sanders is a Democrat -- or at least he'll be running as one in 2020.
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Sanders, a Vermont independent, signed a pledge declaring that he was a Democrat and would serve as one if he won the presidential election, reports say.
New Democratic National Committee rules require candidates to sign the pledge.
"I am a member of the Democratic Party. I will run as a Democrat, accept the nomination of the party, and I will serve as a Democrat if elected," the document says.
More than a dozen candidates have announced plans to seek the White House in 2020.
Per the document, the DNC will have the authority to look into a candidate's past to determine if they are a 'bona fide Democrat' USA Today reports.
On Monday, Sanders filed to run as an independent to defend his Senate seat in 2024.