There were more than 5,000 people at the Bon Secours Wellness Arena, home of the Swamp Rabbits, a minor-league hockey team. That figure is especially impressive because this region is deep Republican red, though the area’s several universities seemed to deliver a number of younger, more liberal attendees.

The first thing you notice at a Sanders rally is the kids. Not the college kids, though there are plenty of those. It’s the little kids in families: fathers carrying Bernie-buttoned kids on shoulders, mothers shepherding kids who wave handmade signs that suggest either parental involvement or extremely precocious concern about tuition bills. The second thing you notice is the gear. Few candidates inspire such clothing devotion as Sanders.

You also notice the demographic make-up pretty quickly—even in the absence of the questions about African American voters that face the Sanders campaign. Clinton’s so-called firewall is built largely of black voters, a group with which she leads Sanders by 30 to 40 points in recent polls. Overall, she leads by more than 20 points in recent South Carolina polls. The Sanders crowd Sunday wasn’t as uniformly Caucasian—or as uniformly 20-something—as some accounts might suggest, but it also falls well-short of the 55 percent of Democratic voters who were black in the 2008 primary.

Sanders’s campaign is well aware of the gap. In Greenville, the first speaker was Garrett McDaniel, a black county councilman from next-door Laurens County. After him came Ben Jealous, the former NAACP president and one of Sanders’s most prominent African American backers. Jealous, in turn, brought out the actor Danny Glover, who delivered a fiery exhortation on Sanders’s behalf. In his stump speech, Sanders talks repeatedly about issues of racism—police violence, mass incarceration, unequal arrest rates for marijuana use, and so on. But these causes often come within the context of the economic issues dearest to Sanders’s heart.

For all the black faces on stage, however, there still aren’t that many in the crowd. Sanders and Jealous also stopped by a black Baptist church in West Columbia earlier in the day, where The New York Times described the response as “muted.”

Standing in line to get into the event, I spoke with Ralph Morton, who was anything but muted—he sported a twinkle in his eye and a gray fu-manchu. “Bernie seems to be a cool guy, straightforward and honest. I say burn, Bernie, burn!” he said. “Hillary thought she had a shoo-in. He got under her skin a couple times.” Morton discounted Clinton’s chances with black voters, noting that she'd let the African American vote escape her once before, in 2008, and drew an analogy with another dynastic candidate who just left the race. “It’s just like Jeb Bush thought he was going to be a shoo-in because of past support. He got toasted.”