Tuesday night’s South Carolina Democratic debate quickly devolved into a shouting match among the seven candidates on stage, leading to low social media grades for CBS’ seemingly overmatched co-moderators.

“CBS Evening News” anchor and managing editor Norah O’Donnell and Gayle King, who co-hosts “CBS This Morning,” co-moderated the debate, which was frequently marked by candidates talking — and often shouting — over each other as they tried to get in a last word and respond to each other’s attacks.

The candidates who participated in the debate were former Vice President Joe Biden; former South Bend, Ind., Mayor Pete Buttigieg; former New York City mayor Mike Bloomberg; business executive Tom Steyer; and U.S. Sens. Bernie Sanders, Amy Klobuchar and Elizabeth Warren.

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King received death threats after her interview with Lisa Leslie on Kobe Bryant’s legacy after the NBA superstar died earlier this month in a helicopter crash, along with seven others.

CBS News co-hosted the debate with the Congressional Black Caucus Institute in Charleston, S.C., only a few days before the critical South Carolina primary on Saturday, Feb. 29.

Earlier Tuesday, U.S. Rep. Tulsi Gabbard’s absence from the debate was all the talk of social media.

Gabbard was not be among the seven Democrats debating in Charleston, although Steyer, who is polling behind Gabbard in the Palmetto State, did.

Steyer qualified for the debate after hitting 18% in a CBS News/YouGov poll in South Carolina released Sunday morning, one day before the Democratic National Committee's deadline to set the stage.

However, in a CNN poll released Monday, Gabbard’s 3% was higher than Steyer’s almost nonexistent numbers.

The Democratic National Committee is already under fire for changing its qualifying rules that allowed Bloomberg to enter debates and primaries late in the 2020 election season.

Gabbard has been running for president since January 2019.

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While the Hawaii congresswoman has polled consistently low in Iowa, New Hampshire and Nevada, she’ll be on the South Carolina ballot Saturday, unlike Bloomberg, who did not qualify for the Palmetto State primary.

Gabbard made headlines last month when she filed a $50 million lawsuit against Clinton, alleging the former secretary of state, U.S. senator and first lady called Gabbard a “Russian asset.”

The suit alleges Clinton “lied about her perceived rival” on Oct. 17, 2019, when Clinton was a guest on a podcast titled “Campaign HQ with David Plouffe.”

»MORE: Gabbard suing Hillary Clinton for $50 million in damages

Clinton said “somebody who is currently in the Democratic primary” is “the favorite of the Russians. They have a bunch of sites and bots and other ways of supporting her so far. And, that’s assuming Jill Stein will give it up, which she might not because she’s also a Russian asset.

“Yeah, she’s a Russian asset.”

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Besides Steyer and Bloomberg, the rest of Tuesday night’s debate field includes Joe Biden, Pete Buttigieg, Amy Klobuchar, Bernie Sanders and Elizabeth Warren.

The debate will be hosted by CBS News and the Congressional Black Caucus Institute, in partnership with Twitter in Charleston, S.C. It starts at 8 p.m. EST.