Each stop on Sanders’s journey through the South doubled as early outreach to a demographic he would desperately need if and when he sought the presidency again.

Read: The establishment strikes back.

Sanders’s agenda—dismantling broken systems and replacing them with ones that benefit working-class people, regardless of race—is intimately bound up with the nation’s civil-rights legacy. But, some argue, Sanders has struggled to clearly articulate that connection in a way that earns black voters’ support.

When Sanders first ran for president, in 2016, he excited white progressives who were not interested in Hillary Clinton’s brand of moderate politics. His base was young and energetic, but it was light on black support. Sure, a small majority of black voters under 30 supported him, but they made up just 3 percent of the black electorate in the primary. Black activists argued that his campaign did not pay enough attention to racial violence and inequities in the criminal-justice system. His speeches were frequently interrupted by members of Black Lives Matter, who sought to push candidates to be more aggressive on racial issues. They attempted similar protests of Clinton but were stymied. (At least on one occasion, they were blocked at the door by Secret Service agents.) Clinton’s events were stage-managed to the finest detail; Sanders’s were more DIY and raucous.

Sanders has admitted that his 2016 campaign was “too white.” Indeed, his inability to excite a large group of voters beyond his majority-white base led to a pummeling across the South. Older black voters knew Clinton; Sanders was the one rolling the boulder uphill. He lost the black vote by 90 percent in Arkansas, by 86 percent in South Carolina, and by 89 percent in Tennessee. In Missouri, where he lost by the slim margin of 0.2 percent, he lost the black vote by 67 percent.

For many voters, the 2016 election was their first introduction to the Vermont senator with the unkempt hair and radical ideas. He knew more people would know his name if he ran again in 2020, but he needed to do more: He needed to hire a more diverse staff, attend events at historically black colleges and universities, speak to black media and black people directly, and, perhaps more than anything, listen to black voices.

He did all that. But despite his efforts, the support never quite materialized. From the South Carolina primary through Super Tuesday, among black voters, Sanders was trounced by former Vice President Joe Biden. Sanders offered a revolution; voters rebuffed it. The black people who did support Sanders tended to be younger—and young people tend to vote at lower rates than older people do.

Tonight, exit polls showed that Sanders lost the black vote in Mississippi by 71 points—84 percent of black voters supported Biden, and just 13 percent supported Sanders. Sanders’s performance among black voters was just 2 percentage points better than it was in 2016. Cable networks called the race as soon as the polls closed: another decisive victory in the South for Biden.