From left, Democratic presidential candidates, former New York City Mayor Mike Bloomberg, former South Bend Mayor Pete Buttigieg, Sen. Elizabeth Warren, D-Mass., Sen. Bernie Sanders, I-Vt., former Vice President Joe Biden, Sen. Amy Klobuchar, D-Minn., and businessman Tom Steyer participate in a Democratic presidential primary debate, Tuesday, Feb. 25, 2020, in Charleston, S.C. (AP Photo/Matt Rourke)

6 Images

Democratic presidential debate in Charleston, S.C.

Seven presidential contenders take part in the 10th Democratic presidential debate on Tuesday night, four days before the Feb. 29 South Carolina primary.

Democratic presidential candidates onstage in Charleston, S.C. From left: Michael R. Bloomberg, Pete Buttigieg, Elizabeth Warren, Bernie Sanders, Joe Biden, Amy Klobuchar and businessman Tom Steyer. (Matt Rourke / Associated Press)

From left, Democratic presidential candidates, former New York City Mayor Mike Bloomberg, former South Bend Mayor Pete Buttigieg, and Sen. Elizabeth Warren, D-Mass., walk onto the stage to participate in a Democratic presidential primary debate, Tuesday, Feb. 25, 2020, in Charleston, S.C. (AP Photo/Matt Rourke)

Michael R. Bloomberg, Pete Buttigieg and Elizabeth Warren before the debate. (Matt Rourke / Associated Press)

From left, Democratic presidential candidates, Sen. Elizabeth Warren, D-Mass., Sen. Bernie Sanders, I-Vt., former Vice President Joe Biden, Sen. Amy Klobuchar, D-Minn., and businessman Tom Steyer, stand on stage before a Democratic presidential primary debate at the Gaillard Center, Tuesday, Feb. 25, 2020, in Charleston, S.C., co-hosted by CBS News and the Congressional Black Caucus Institute. (AP Photo/Patrick Semansky)

Onstage in Charleston. (Patrick Semansky / Associated Press)

From left, Democratic presidential candidates, Sen. Bernie Sanders, I-Vt., former Vice President Joe Biden, talks before a Democratic presidential primary debate, Tuesday, Feb. 25, 2020, in Charleston, S.C. (AP Photo/Matt Rourke)

Bernie Sanders and Joe Biden. (Matt Rourke / Associated Press)

From left, Democratic presidential candidates, former Vice President Joe Biden, Sen. Amy Klobuchar, D-Minn., and businessman Tom Steyer, participate in a Democratic presidential primary debate at the Gaillard Center, Tuesday, Feb. 25, 2020, in Charleston, S.C., co-hosted by CBS News and the Congressional Black Caucus Institute. (AP Photo/Patrick Semansky)

Joe Biden, left, Amy Klobuchar and Tom Steyer. (Patrick Semansky / Associated Press)

CHARLESTON, SOUTH CAROLINA - FEBRUARY 25: Democratic presidential candidate former Vice President Joe Biden speaks as Sen. Bernie Sanders (I-VT) (L) loo during the Democratic presidential primary debate at the Charleston Gaillard Center on February 25, 2020 in Charleston, South Carolina. Seven candidates qualified for the debate, hosted by CBS News and Congressional Black Caucus Institute, ahead of South Carolina’s primary in four days. (Photo by Win McNamee/Getty Images)

Bernie Sanders and Joe Biden. (Win McNamee / Getty Images)

1/6

Democratic presidential debate in Charleston, S.C.