"I got to be honest and I say it with love, the DNC process is stifling debate at a time when we need it most," Bennet said. "We're rewarding celebrity candidates with millions of Twitter followers, billionaires who buy their way onto the debate stage, and candidates who have been running for president for years."
He made those comments during the DNC's summer meeting, attended by hundreds of party delegates.
"It forces campaigns to [fork] over millions of dollars to Facebook — the same platform that let the Russians interfere in 2016 instead of harnessing the resources to talk to voters," Bennet went on.
Bennet wasn't the first Democratic candidate to criticize the DNC's increasingly prohibitive criteria – including thresholds for donor counts and polling numbers – but his latest remarks seemed to be the most confrontational.
DNC War Room director Adrienne Watson defended the rules later on Friday, saying, “The debate rules have been public for months, and candidates have been given more opportunities and more time to qualify for debates than in previous cycles," she said in a statement obtained by Fox News.
Bennet's comments came two days after Washington Gov. Jay Inslee dropped out of the unprecedentedly crowded race partially because, the senator said, Inslee couldn't qualify for an event on climate change — his signature campaign issue.
"Think about that for a moment: the climate change candidate didn't qualify for the climate change town hall. If we wanted to be the party that excluded people, we'd be Republicans," Bennet added before telling delegates he wouldn't be on the debate stage in Houston next month.
Bennet's comments seemed to echo those of Montana Gov. Steve Bullock, who accused Democratic megadonor Tom Steyer of buying his way onto the debate stage.
"We’re kidding ourselves if we’re calling a $10 million purchase of 130,000 donors a demonstration of grassroots support,” Bullock said last week. “It’s not serving the candidates, and it sure isn’t helping the voters who will actually decide this election.”
Steyer had announced that he received campaign contributions from at least 130,000 individual donors, thereby meeting one of the DNC's two criteria to make the stage at the third and fourth rounds of debates, which will be held in September and October.
But Steyer apparently wasn't satisfied with the DNC's requirements either, releasing a statement on Friday that blasted the party's polling requirement.
Rep. Tulsi Gabbard, D-Hawaii, also decried the debate criteria, saying in a statement Friday: "The campaign ... is calling on the Democratic National Committee to revise their list of debate qualifying polls in light of numerous irregularities in the selection and timing of those polls, to ensure transparency and fairness."
Perez previously defended raising the polling and fundraising thresholds, saying: "If you can't run an effective grassroots campaign in the year 2020, in today's era, you're not going to be able to win the presidency."
"And what our dual threshold has done is to give additional opportunity to the candidates," he told CBS News.
"What we wanted to do was make sure that we had multiple opportunities where they could present their vision to the American people," Perez added. "And then, as it happens in every primary cycle, you've got to demonstrate progress, and that's what September is about."
Fox News' Paul Steinhauser contributed to this report.