Here's what you need to know about Thursday's 2020 Democratic presidential debate

Key Points
  • Seven Democratic candidates hit the debate stage Thursday night at Loyola Marymount University in Los Angeles.
  • The event is taking place with a little more than a month until the first primary nominating contest in Iowa.
  • Joe Biden, Bernie Sanders, Elizabeth Warren and Pete Buttigieg have emerged as the top contenders for the nomination, according to polling.
Democratic presidential hopefuls, Mayor of South Bend Pete Buttigieg (L), Massachusetts Senator Elizabeth Warren (C) and former Vice President Joe Biden, arrive onstage for the fifth Democratic primary debate of the 2020 presidential campaign season co-hosted by MSNBC and The Washington Post at Tyler Perry Studios in Atlanta, Georgia on November 20, 2019.
Saul Loeb | AFP | Getty Images

Seven 2020 Democratic presidential candidates hit the debate stage on Thursday night with a little more than a month until primary nominating contests start.

The top of the 15-person field has taken clearer shape in the final weeks before the Iowa caucuses in February. In what was the most diverse presidential field in history, the race's leaders skew older and whiter than the field as a whole.

Several hopefuls are  looking for a breakout moment at the debate, hosted by PBS NewsHour and Politico. The event at Loyola Marymount University in Los Angeles started at 8 p.m. ET.

The debate features, in alphabetical order:

  • Former Vice President Joe Biden
  • South Bend Mayor Pete Buttigieg
  • Sen. Amy Klobuchar, D-Minn.
  • Sen. Bernie Sanders, I-Vt.
  • Billionaire activist Tom Steyer
  • Sen. Elizabeth Warren, D-Mass.
  • Entrepreneur Andrew Yang

The standards for qualifying for the debates have become tougher as the nominating contests draw closer. Two hopefuls who took the stage in November's debate — Sen. Cory Booker, D-N.J., and Rep. Tulsi Gabbard, D-Hawaii — failed to hit the threshold for December's edition (though Gabbard said she would skip the event for a number of reasons, even if she qualified).

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The House vote Wednesday night to impeach President Donald Trump for abuse of power and obstruction of Congress will likely come up during the debate. The senators still in the race — Sanders, Warren, Klobuchar, Booker and Sen. Michael Bennet, D-Colo. — will likely have to return to Washington in the weeks before Iowa for the trial on whether to remove Trump from office.

Biden, Sanders and Warren top an average of national primary polls, with about 28%, 19% and 15% of support, respectively, according to RealClearPolitics. Buttigieg follows with 8% nationally. The mayor from Indiana has jumped to the top spot in an average of Iowa polls with 22% of support, just ahead of Sanders, Biden and Warren.

Former New York City Mayor Mike Bloomberg's entry into the race has caused some reverberations. The billionaire has already spent more than $100 million on ads and garnered about 5% of support in an average of national polls.

The candidates have jockeyed for position in California, which will award a trove of delegates on March 3, or Super Tuesday. Sanders, in particular, boosted his presence in the state recently as he drew about even with Biden in an average of polls there.

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Health care has played a huge role in every debate and likely will again Thursday. Sanders and Warren have defended their plans for a single-payer "Medicare for All" system as Biden, Buttigieg and Klobuchar push to boost coverage with a public insurance option.

A clash between Warren and Buttigieg — which contributed to Buttigieg releasing his clients from his time at consulting company McKinsey and Warren divulging decades of legal cases — could spill over into the debate, as well.

— CNBC's Lauren Hirsch contributed to this report

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