By Agence France-Presse
Twenty Democrats will take the stage in prime time on June 26 and 27 in Miami -- in two groups of 10 -- as they battle to become the nominee who will challenge President Donald Trump for the White House next year.
Former US vice president Biden, the unequivocal frontrunner, and liberal senator Sanders, who is polling in second, will be among 10 candidates sharing the stage on the second night.
They will be joined by South Bend, Indiana Mayor Pete Buttigieg, who has surged from obscurity into fourth place in early polling, and fifth place Senator Kamala Harris, who launched her campaign to strong buzz but has struggled to maintain momentum.
That leaves liberal Senator Elizabeth Warren, who is polling in third place and whose star has risen recently, as the clear headliner on the first night.
Her primary on-stage rivals will be ex-congressman Beto O'Rourke and Senator Cory Booker.
With the opening debate now set, the political stakes of the primary race were becoming clearer.
Warren squares off against several lower-polling rivals scrambling for a breakout moment.
Joining her will be New York Mayor Bill de Blasio; former San Antonio mayor Julian Castro, the only Latino in the 2020 race; former congressman John Delaney; congresswoman Tulsi Gabbard; Washington Governor Jay Inslee; Senator Amy Klobuchar; and congressman Tim Ryan.
But the second night's broadcast may ultimately score more eyeballs given it features the lion's share of popular candidates.
In addition to the top-tier candidates, Day 2 will include Senator Michael Bennet; Senator Kirsten Gillibrand; former Colorado governor John Hickenlooper, congressman Eric Swalwell; best-selling author on spirituality Marianne Williamson; and technology entrepreneur Andrew Yang.
The debates will give unprecedented public exposure for candidates like Williamson and Yang, who are new to the political realm.
Yang, a 44-year-old Asian-American, has proposed a Universal Basic Income of $1,000 per month for every American adult to help address the growing threat of automation.
"My dreams are coming true," he tweeted after the debate line-up was announced.
The debate, two hours per night, will air live on NBC, MSNBC and Telemundo.
A manual random drawing to determine the line-ups was held at NBC News headquarters in New York, conducted in the presence of Democratic National Committee (DNC) officials and candidate representatives.
The 2020 Democratic race features the largest primary field in modern history, and the party was not able to accommodate all candidates.
Congressman Seth Moulton, Montana Governor Steve Bullock and Mayor Wayne Messam of Miramar, Florida failed to meet the polling and fund-raising criteria set by the DNC and were not invited to attend.