As former Vice President Joe Biden moves closer to securing the Democratic presidential nomination, supporters of rival Bernie Sanders are delivering a warning. Jon Levine reports for the New York Post.

The Bernie Bros are vowing revenge.

As the presidential campaign of Sen. Bernie Sanders continues to crash and burn, the socialist’s most hard-core supporters are vowing they will never vote for Joe Biden at the ballot box — even if that means handing Trump a second term.

“We will never – NEVER boost or support Joe Biden or defend his abysmal record and terrible policy positions,” Henry Williams, executive director of The Gravel Institute, told The Post. “We will tell people, as we always have, to vote their conscience and to make decisions based on the interests of all the world’s oppressed people … I do expect a massive exodus from the Democratic Party.”

Williams, along with David Oks and Henry Magowan, are the driving forces behind the brief presidential campaign of Mike Gravel, an 89-year-old former Alaska senator who left the race in August. The trio then became enthusiastic Bernie Bros.

“I don’t know if I could vote for Biden,” said a high-profile local Democratic Socialist. “Biden is just an old white guy who inspires nobody. I sincerely think he will lose the electoral and popular vote and I know I won’t be voting for him in New York.”

The grumbling from Sanders die-hards is no idle threat. A whopping 12% of them voted for Trump in 2016, according to an analysis by Cooperative Congressional Election Study. That added up to roughly 216,000 voters in Michigan, Pennsylvania and Wisconsin, exit polls showed. Trump’s combined margin of victory in those states was 77,744.