Democratic presidential candidate Sen. Bernie Sanders (I-VT) exits after delivering remarks at a campaign function in the Marvin Center at George Washington University on June 12, 2019 in Washington, DC.

NBC News set the lineup for the first 2020 Democratic presidential debate on Friday, and the two highest-polling candidates — former Vice President Joe Biden and Sen. Bernie Sanders — will share the stage.

The debate, sanctioned by the Democratic National Committee, will take place in Miami on June 26 and 27 at 9 p.m. ET. NBC News, MSNBC and Telemundo will host it.

Wednesday, June 26:

Sen. Cory Booker, D-N.J.

Former Housing and Urban Development Secretary Julian Castro

New York Mayor Bill de Blasio

Former Rep. John Delaney

Rep. Tulsi Gabbard, D-Hi.

Washington Gov. Jay Inslee

Sen. Amy Klobuchar, D-Minn.

Former Rep. Beto O'Rourke

Rep. Tim Ryan, D-Ohio

Sen. Elizabeth Warren, D-Mass.

Thursday, June 27:

Former Vice President Joe Biden

Sen. Michael Bennet, D-Colo.

South Bend, Indiana, Mayor Pete Buttigieg

Sen. Kirsten Gillibrand, D-N.Y.

Sen. Kamala Harris, D-Calif.

Sen. Bernie Sanders, I-Vt.

Former Colorado Gov. John Hickenlooper

Rep. Eric Swalwell, D-Calif.

Author Marianne Williamson

Entrepreneur Andrew Yang

The debate will offer one of the first major opportunities for the 20 candidates to set themselves apart from rivals in a crowded field. While contenders have found themselves campaigning in early nominating states at the same time, direct confrontation over policy differences has so far been limited — with some exceptions.

NBC News divided the qualifiers into two groups, those who averaged 2% or higher in public opinion polls through June 12 and those who did not. The network then drew randomly from those pools to sort the qualifiers into two groups of 10.

Four candidates — Montana Gov. Steve Bullock; former Alaska Sen. Mike Gravel; Miramar, Florida, Mayor Wayne Messam and Rep. Seth Moulton, D-Mass. — did not meet the standards to qualify for the debate. Bullock has slammed the DNC for determining that he did not make the cut. His campaign released an ad Friday in which a Montanan calls it "horses--t" that Bullock failed to qualify.

The primary election so far has featured minimal direct clashes between candidates, though some contenders have started to target Biden, who has led just about every major national and early voting state poll. Sanders has criticized Biden over his stances on trade and climate change. O'Rourke, meanwhile, said the former vice president would be a "return to the past."

In addition, some of the more centrist candidates such as Delaney and Hickenlooper have criticized Sanders for his self-proclaimed democratic socialism and sweeping policy plans.

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