A "Bernie or Bust" rap song echoed throughout Philadelphia City Hall on Tuesday as hundreds of Bernie Sanders supporters gathered around a small stage and sang together in unison.
Sanders fans felt reenergized after the first night of the Democratic National Convention, despite the fact Sanders vowed to "do everything I can" to make a Hillary Clinton presidency happen.
"You know what, it's not over," voter Cory Bohn told CBS News at the event. "I believe he's waiting for us to do something."
The 38-year-old traveled to Philadelphia from Santa Rosa, California, to urge delegates not to back Clinton.
Sporting a red, white and blue "Ring in the Political Revolution" t-shirt, Bohn cheered alongside dozens of other die-hard Sanders supporters.
Co-founder of the "Bernie or Bust" movement Victor Tiffany told the group they're making a commitment.
"It's not just, 'Oh, we're going to vote for Hillary,'" he shouted from the platform. "We're coming after her. If [Sanders] doesn't come out of this convention as the nominee -- the gloves come off."
The crowd roared with applause.
It was similar to the energy that filled the Wells Fargo Center Monday night when Sanders supporter Sarah Silverman took the stage to throw her support to Clinton, which was greeted with loud booing from Sanders fans.
"To the 'Bernie or Bust' people: You're being ridiculous," she scolded from the podium.
"I thought it was rude," Bohn said. "Everybody has a right to their own opinion. I'm sure it was frustrating, but calling us ridiculous? We believe in something higher."
Pauline Zager, a 36-year-old from Doylsetown, Pennsylvania, described her passion for the movement.
"I'm not here just because I'm trying to make a point or because I'm a sore loser," she said. "The world needs Bernie Sanders, and the world is speaking out in increasing numbers louder and louder to be heard."
While other members of the "Bernie or Bust" group proudly said they have been "feeling the Bern" since day one, Zager admitted she hadn't even heard of Sanders until a couple of months ago -- the day a bird landed on his podium, the moment went viral, and "Birdie Sanders" was born.
"I started learning and listening," said Zager, explaining that she's particularly concerned about climate change. "I was flabbergasted that there happened to be someone like him who existed. It breaks my heart that the Democratic Party is throwing that away."
No one understands Zager's point more than New Hampshire resident Emily Weber.
The 31-year-old, who volunteered for the Vermont senator's campaign, said the Democratic National Committee is to blame for Sanders not getting the nomination.
"Everyone's been calling us conspiracy theorists, but there's finally proof we weren't wrong," said Weber, referring to the leaked DNC email scandal. "I believe the election was robbed from him."
Tiffany told supporters to go out and vote for Sanders in November no matter what.
At this point, the "Bernie or Bust" backers have made up their minds, and say there's nothing Clinton can do to change them -- though Sanders himself says they should.
"I haven't trusted her for a long time," Weber said. "She always has her best interests at heart and not everyone else's."
A frustrated Tiffany didn't sugarcoat his opinion on the matter.
"It's clear Donald Trump wants to get blood on his hands, but Hillary Clinton is already covered head to toe -- with blood from Iraq and Libya," he said.