Democratic National Committee chairman Tom Perez on Sunday defended stricter criteria that has led to a tightening in the number of candidates scheduled to appear in Thursday's presidential primary debate.
"It's always been up to the voters," Perez said on ABC's "This Week."
"I think our process has been the most fair, transparent, inclusive process in the history of the Democratic primary ... Our field is deep. But we're reaching a point now where voters are differentiating. And that's what it's about. And candidates have to demonstrate progress as we get closer and closer to Iowa and New Hampshire."
Ten candidates are set to square off Thursday in a three-hour debate to be broadcast on ABC and Univision.
To qualify, candidates needed to win support of 2 percent of voters in four polls approved by the DNC and receive donations from 130,000 individual donors.
After debates in June and July in which 20 candidates squared off on two nights of debate each, the Sept. 12 debate is the first to reflect the higher fundraising and polling standard.
The threshold to qualify in the NBC debates in June and CNN debates in July were meeting the 1 percent polling minimum and receiving 65,000 individual campaign contributions.
"Two percent, quite frankly, is — is a very reasonable bar," Perez said.
Sen. Michael Bennet (D-Colorado) last month criticized the party for narrowing the field.
"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," Bennet said at the DNC's summer meeting. "It forces campaigns to force 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.”
Sen. Kirsten Gillibrand (D-New York) dropped out of the presidential campaign after she had failed to qualify for the third debate. New York City Mayor Bill de Blasio said he is still a candidate despite failing to qualify.