Former U.S. Vice President Joe Biden greets House Majority Whip James Clyburn during a fish fry event in Columbia, S.C. on June 21, 2019.

Former U.S. Vice President Joe Biden, 2020 Democratic presidential candidate, right, greets House Majority Whip James Clyburn, a Democrat from South Carolina, during Jim Clyburn’s World Famous Fish Fry event in Columbia, South Carolina, U.S., on Friday, June 21, 2019. Joe Biden is trying to make amends after a misstep over his history of working alongside segregationist senators as he heads for a weekend of campaign events in South Carolina, where African-American voters are crucial to victory in the state’s Democratic primary. Photographer: Al Drago/Bloomberg via Getty Images