(Bloomberg) -- Democratic front-runner Joe Biden will face Senators Bernie Sanders and Kamala Harris in the second night of the party’s two-part presidential primary debate in Miami later this month.

Senator Elizabeth Warren will appear in another group of candidates on the first night, when she will be matched against former Representative Beto O’Rourke and Senator Amy Klobuchar of Minnesota. The Democratic National Committee has selected 20 of the 23 candidates for the presidential nomination to participate in the forums. Ten contenders will be on stage each night, June 26 and June 27.

The division is likely to disappoint candidates who won’t be on stage with Biden. Their debate may not draw as much attention from the media and voters, nor will they have the opportunity to directly take on the former vice president.

NBC, which is hosting the debate, randomly selected the candidates for each night to ensure a mix of high-polling and low-polling contenders. The split is designed to avoid making one night an all-star debate and the other an undercard.

The June 26 event will feature:

1. Senator Cory Booker of New Jersey2. Representative Julian Castro of Texas3. Mayor Bill de Blasio of New York4. Former Representative John Delaney of Maryland5. Representative Tulsi Gabbard of Hawaii6. Governor Jay Inslee of Washington7. Senator Amy Klobuchar of Minnesota8. Former Representative Beto O’Rourke of Texas9. Representative Tim Ryan of Ohio10. Senator Elizabeth Warren of Massachusetts

The June 27 event will feature:

1. Senator Michael Bennet of Colorado2. Former Vice President Joe Biden3. Mayor Pete Buttigieg of South Bend, Indiana4. Senator Kirsten Gillibrand of New York5. Senator Kamala Harris of California6. Governor John Hickenlooper of Colorado7. Senator Bernie Sanders of Vermont8. Representative Eric Swalwell of California9. Spiritual healer Marianne Williamson10. Entrepreneur Andrew Yang

To qualify for the debates, candidates were required to hit a threshold of 1% in multiple major polls or collect donations from 65,000 people in at least 20 states. The candidates who didn’t make the cut are Montana Governor Steve Bullock; Wayne Messam, the mayor of Miramar, Florida; and Massachusetts Representative Seth Moulton.

The DNC intended that the rules would be a way to include hopefuls who might have grassroots support but hadn’t yet broken through more widely. That also means each stage will be crowded. Biden, who’s likely to be the central target of his debate stage and possibly the other night, said this week that he was skeptical about the format.

“It’s a little bit of an exaggeration to call it a debate because there’s not really much time,” he said Wednesday in Iowa. “It’s a little confusing, but it’s the right thing for the Democratic Party to do to reach out and give everybody who wants a shot of running a shot.”

The moderators for the two nights will be Jose Diaz-Balart, Savannah Guthrie, Lester Holt, Rachel Maddow and Chuck Todd.

To contact the reporter on this story: Jennifer Epstein in Washington at jepstein32@bloomberg.net

To contact the editors responsible for this story: Joe Sobczyk at jsobczyk@bloomberg.net, Max Berley, Laurie Asséo

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