Did Jesse Jackson and Al Sharpton, having lost their own bids, fail to support the Demonrat nominee? No. These guys will back whomever their socialist fellow conspirators nominate. They would do so even if the Republicans nominated a black (remember Michael Steele in MD?).
Different scenarios. Neither Jackson nor Sharpton had a snowball’s chance of winning. Obama IS winning. If he gets robbed at the convention by machine politics, large segments of the black voter population will not turn out, even if Jackson and Sharpton ultimately back Hillary. Neither of those venerable reverends have the same clout today that they did years ago.