Bernie Sanders’ endorsement of Joe Biden hasn’t gone over well with the socialist senator’s supporters, who see their candidate’s capitulation as a betrayal of his values.

Sanders made a surprise appearance in a livestream with Biden on Monday, to give his full endorsement to a candidate he’d once described as an architect of “disastrous” trade policies, a stooge for credit card companies, and part of “the establishment that is working frantically to try and defeat us.”

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“We’ve got to make Trump a one-term president and we need you in the White House,” Sanders said to Biden on Monday, before calling on his supporters to back the former vice president.

To Sanders’ vocal base of left-wing supporters, the endorsement was a punch to the gut. Many, including former press secretary Briahna Joy Gray, refused to follow their candidate onto team Biden. “With the utmost respect for Bernie Sanders, who is an incredible human being & a genuine inspiration, I don't endorse Joe Biden,” Gray tweeted.

With the utmost respect for Bernie Sanders, who is an incredible human being & a genuine inspiration, I don't endorse Joe Biden. I supported Bernie Sanders because he backed ideas like #MedicareForAll, cancelling ALL student debt, & a wealth tax. Biden supports none of those. — Briahna Joy Gray (@briebriejoy) April 13, 2020

David Sirota, Sanders’ most senior adviser until Monday, spent the day arguing with Twitter critics (at one point calling pundit Michael Tracey a “total d*ck”) who blamed the senator’s campaign for its failure to beat Biden. When Sanders gave Biden the thumbs-up, Sirota turned to history to explain “how steep the odds” against his boss were.

“In the last 68 years, a party’s outgoing or immediate past vice president has never run for president and not won his party's nomination,” he tweeted, the grim resignation palpable. “Never. Not once.”

In the last 68 years, a party's outgoing or immediate past vice president has never run for president and not won his party's nomination. Never. Not once.This does not absolve us of any responsibility for losing the primary, but it gives you a sense of how steep the odds were. — David Sirota (@davidsirota) April 13, 2020

Sanders’ fans and left-wing commentators made their disappointment and rage known. “#BernieSanders has endorsed Joe Biden,” tweeted ‘Redacted Tonight’ host Lee Camp. “Apparently no one told him that political revolutions do not ‘endorse’ the complete opposite of everything they stand for.”

I have been called a cultist thousands of times over the last year. Watch me serenely ignore Bernie Sanders' exhortation to support Joe Biden 😌 — Meagan Day (@meaganmday) April 13, 2020

The left stays losing every time it trots out this tired line about how bad orange man is the most dangerous president in modern history and not merely the logical conclusion of the sclerosis and rot of establishment politics — Anna Khachiyan (@annakhachiyan) April 13, 2020

I wish Bernie Sanders were the egomaniac his dishonest haters claim he was because then he'd still be in the race. I assume that he thinks he's doing this for the sake of the party but uniting behind someone who will surely lose to Trump isn't a good idea. — Katie Halper (@kthalps) April 13, 2020

To commenters on the right, the move was no surprise. After leading a campaign that came within inches of defeating Hillary Clinton in 2016, Sanders backed Clinton, much to the anger of his most devoted followers. Moreover, Sanders has repeatedly described Trump as the “most dangerous president in modern history,” and the socialist senator was unlikely not to back his party’s eventual nominee.

Bernie Sanders just endorsed everything he was running against, just like he did in 2016What a total fraud — Ryan Saavedra (@RealSaavedra) April 13, 2020

Sanders is perhaps the most recognizable face of the American left, and a powerful ally to Biden. Whether his supporters accept his defeat and switch their allegiance en masse to the former VP will be definitively revealed in November. Until then, expect the rage to keep flowing on Twitter.

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