Seven candidates qualified for the sixth Democratic 2020 presidential debate, scheduled for Dec. 19 at Loyola Marymount University in Los Angeles, California.

Driving the news: All qualifying candidates have said on Twitter they won't attend the debate unless the host, Loyola Marymount University, reaches a deal with its workers in an ongoing labor dispute.

How it works: December's polling requirements included at least 4% of support in at least four DNC-approved national or early-state polls.

Candidates could also qualify by hitting 6% in two approved early-state polls.

Contenders need at least 200,000 unique donors, with a minimum of 800 donors in 20 states.

The event will be moderated by Politico's Tim Alberta and PBS' Judy Woodruff, Amna Nawaz and Yamiche Alcindor.

Candidates who will be on stage:

Candidates who met donor qualifications, but not polling requirements:

Candidates that did not meet any qualifications:

Author Marianne Williamson, Former Gov. Deval Patrick, Former Rep. John Delaney, Former New York Mayor Michael Bloomberg and Sen. Michael Bennet.

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