U.S. Democratic presidential candidate Bernie Sanders speaks to a large crowd of supporters in Carson, California, U.S., May 17, 2016. Reuters/Lucy Nicholson Sen. Bernie Sanders is set to campaign with presumptive Democratic nominee Hillary Clinton Tuesday at a rally in New Hampshire — officially beginning Democrats' long-awaited unity tour two weeks before the Democratic National Convention in Philadelphia.

But the Sanders subreddit, /r/SandersForPresident, isn't having any of it.

The page lit up with angry supporters Monday morning, after both campaigns confirmed the joint appearance in Portsmouth in near tandem press releases.

Some turned on Sanders as soon as the news broke.

"This is disgusting but I suspected it was coming. This is where Bernie and I part ways," user Grizzly_Madams wrote. "He's still a good man and he still deserves credit for putting up a good fight and for revealing how horribly corrupt the Democrats are but I don't agree with his decision to now work with those who stole this nomination from us and who are actively fighting to strip power from progressives."

Addressing Sanders, user Donkeybutternipple wrote, "I know you have to but we don't have to vote for her," attacking Clinton for not releasing transcripts of her paid speeches before major financial institutions and calling her a "Wall Street whore."

Many felt hurt by the news.

"Of course it hurts. Betrayal usually hurts," user FIYPProductions wrote. "If he endorses her he's going back on everything he claimed to be standing for. Yes, I know he said he would endorse the Dem nominee, but if he will support Hillary simply to fall in line with identity politics then he is no longer the 'for the people' person he claims to be."

User MaddSim expressed anger at Sanders.

"Frankly, I'm outraged that he would do this at all, let alone before the convention," MaddSim wrote. "Even if it isn't an endorsement, it might as well be unless he's going to debate her, which obviously isn't going to happen. He tweeted about Wall St. several times yesterday. To then appear with her is just astonishing to me."

Others were incredulous — concocting conspiracy theories about how the news was an elaborate scheme created by "trolls."

"Don't assume anything yet!!" user Ozanize wrote in a thread.

"We can expect her campaign and the MSM to twist this," Ozanize wrote, referring to Clinton and the mainstream media. "Don't buy the hype."

r/SandersForPresident holding out hope that @BernieSanders/@HillaryClinton joint rally isn't an endorsementpic.twitter.com/ErSXvJ9rfB https://pbs.twimg.com/media/CnFQkeEVIAEH0A9.jpg:large " data-type="twitter">

To be sure, there were comments from supporters who said Sanders' endorsement was welcome news.

"I know this isn't a popular opinion on this sub, but I'm excited for this to happen," user carrotbowrote.

But a number continued their vow to be "Bernie or Bust," saying Sanders' endorsement does not change their decision to not vote for Clinton.

"It makes no difference to me if Bernie endorses her or not, I'm still not voting for Hillary," user Eternally65 wrote. "I'm writing in Bernie."