Bernie Sanders just got trounced in South Carolina by Hillary Clinton. Now what?

Hillary Clinton beat Bernie Sanders overwhelmingly in the South Carolina Democratic primary, taking almost three-quarters of the vote. She owes her victory to African-American voters, who exit polls found supported Clinton over Sanders in every age group—including young black voters, with whom the Sanders campaign had hoped to break through.

So what happened in South Carolina? The Sanders campaign was putting a nominal effort into winning the state as recently as a week or two ago. At that point, the race appeared to be all but locked up for Clinton. Then her campaign ran into some trouble when, less than a week before the primary, an activist in South Carolina confronted the candidate about her use of racially charged terms in the past. Some speculated that might hurt her with African-American voters.

But it probably did little to change the dynamics of the race. Exit polling suggests that a huge majority of voters made up their minds well in advance of the primary. So Sanders’ disadvantage with the Palmetto State’s black voters was probably locked in pretty early. This may be why the Sanders campaign effectively gave up on the state last week and ramped up its efforts in Super Tuesday states, where he’s more competitive.

But Hillary’s staying power with African-American voters should worry Sanders. If he continues to lose the black vote by such overwhelming margins, he may not have much of a shot at the nomination at all.

Before South Carolina, polling guru Nate Silver attempted to chart a path for Sanders to the nomination. He found that Sanders can cede the Southern states, which have more diverse Democratic electorates, only if he wins almost everywhere else by considerable margins. That’s an extremely narrow path to the nomination.

The only other option is to compete in more states, and that means winning black voters. What else could Sanders do to persuade them? A lot.

For starters, he could reverse his position on reparations. The senator has based his campaign on redefining what is possible in Washington, including promising free public college and universal health care. He told Fusion in January that passing a reparations bill just wasn’t realistic.

In addition, he could draw sharper contrasts with Clinton on issues that disproportionately hurt African-Americans, like federal marijuana prohibition and welfare reform.

But probably the most important thing he can do is fully embrace the national movement for black lives and demonstrate to the legions of black Americans organizing under that banner that he is an ally in elevating their voices and their demands.

There is one upside for the Sanders campaign after the big loss in South Carolina: Most primary campaigns that hit early bumps don’t have the fundraising advantage he has. He’ll have more opportunities to shift his message before it’s too late. The question is: Will he?