Biden is the only one who can hold the Blacks. That's the take away from SC. Buttigieg and Klobuchar would drive blacks away, Warren, too, I'd say, but maybe she has a chance to win MA.
I think Trump's campaign to win Black voters has them scared.
All they have to do is keep Bernie from winning on the first ballot. Keep it close enough to steal.
Candidates dropping out make any primary vote counting fraud less obvious. That's why Klobuchar endorsed Biden.