MANCHESTER, New Hampshire — Supporters of Sen. Bernie Sanders (I-VT) booed former South Bend, Indiana, Mayor Pete Buttigieg as he appeared on CNN to speak to his own supporters as the results of the closely-fought New Hampshire Democratic primary rolled in.

The crowd began by booing, then burst into chants of “Bernie Beats Trump!”.

At the time of his speech, Sanders held a narrow lead of less than 2% over Buttigieg, with over 85% of the vote counted. Buttigieg appeared on a giant screen above the 1,200 Sanders supporters at the Southern New Hampshire University Field House as the crowd nervously anticipated the final result — and the result was an outpouring of frustration.

The animosity between the two campaigns is growing.

Sanders has attacked Buttigieg as a tool of rich donor; Buttigieg has attacked Sanders’s socialist policies, in particular “Medicare for All.”

Those tensions only became more intense after the Iowa caucuses, in which Sanders won the popular vote, but Buttigieg narrowly won more “state delegate equivalents” — spots at next month’s state Democratic Party convention.

Buttigieg declared victory prematurely before departing for New Hampshire, and Sanders fans accused him of cheating because an app made by a company that had also worked for Buttigieg was blamed by state Democratic Party officials for slowing the count.

Buttigieg attacked Sanders again, indirectly, in his speech in New Hampshire, using a familiar line from the campaign trial. “In this election, we have been told by some you must either be for revolution or you are for the status quo. But where does that leave the rest of us?”

In his own victory speech, delivered as the news networks finally called the race, Sanders thanked Buttigieg and the other contenders, and drew cheers from the crowd when he declared that he had won in Iowa.

Joel B. Pollak is Senior Editor-at-Large at Breitbart News. He earned an A.B. in Social Studies and Environmental Science and Public Policy from Harvard College, and a J.D. from Harvard Law School. He is a winner of the 2018 Robert Novak Journalism Alumni Fellowship. He is also the co-author of How Trump Won: The Inside Story of a Revolution, which is available from Regnery. Follow him on Twitter at @joelpollak.