NBC has announced how it will divvy up the 20 Democratic candidates for the first debate of the 2020 election campaign, which will be held over two nights in Miami later this month.

The lineup for the first two-hour session on June 26 features Elizabeth Warren, Cory Booker, Beto O'Rourke, Amy Klobuchar, Julian Castro, Bill de Blasio, John Delaney, Tulsi Gabbard, Tim Ryan and Jay Inslee.

The lineup for the next night features Bernie Sanders, Kamala Harris, Joe Biden, Pete Buttigieg, Michael Bennet, Marianne Williamson, Eric Swalwell, Kirsten Gillibrand, Andrew Yang and John Hickenlooper.

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The Democratic National Committee says it divided the candidates at random but ensured that contenders considered front-runners would not be stacked on one night to avoid the impression that one night was more important than the other.

Montana Gov. Steve Bullock was the most high-profile candidate left off the list. He failed to reach the party's polling or grassroots fundraising thresholds.

U.S. Rep. Seth Moulton of Massachusetts, former U.S. Sen. Mike Gravel of Alaska and Miramar, Florida, Mayor Wayne Messam were among the others who missed the threshold for the debate.