It was a big day for Sen. Bernie Sanders and South Carolina’s Legislative Black Caucus, so Brenda Lee Pryce carted her family’s china to Mount Moriah Baptist Church early, then donned an apron to make sure the chicken salad, croissants and pound cake were up to par and other details were perfect.

When Sanders arrived that day, April 18, he spoke for a half-hour about prison reform, economic inequality and educational disparities. But for Pryce, the most telling thing was what he said to her and the other volunteers darting in and out of the kitchen. Namely, nothing.

“I was surprised that his staff didn’t have him go back there, or that he didn’t do it on his own,” said Pryce, a former state legislator. “They just need some manners. We’re Southerners. We’re going to serve you something nice. We’re going to be pleasant, but you better believe there’s power in that kitchen.”

As the 20-plus Democratic hopefuls traipse across South Carolina, black voters are absorbing more than policy positions and applause lines. They’re also taking note of social miscues and ignored niceties that, as Pryce said in an interview, “show you’re coming to the black community just because you have to.”

In a testament to that community’s importance, at least two presidential candidates — former vice president Joe Biden and South Bend, Ind., Mayor Pete Buttigieg — are heading to South Carolina this weekend. Biden remains popular with many black voters, while some have expressed reservations about Buttigieg, but the visits are an important moment for both.

Several candidates, not just Sanders (I-Vt.), have struggled to close the deal in South Carolina. Fellow members of Alpha Kappa Alpha Sorority in the state have asked Sen. Kamala D. Harris (D-Calif.) how they can help her campaign and say they’ve heard little but silence in return. Staffers for Sen. Cory Booker (D-N.J.) have argued with local organizers over scheduling delays.

Former congressman Beto O’Rourke (D-Tex.) has talked extensively about his privilege as a white man, but some black voters at his events complain that he hasn’t offered concrete solutions to address racial disparities. And several of the presidential campaigns have angered their South Carolina-based temporary staffers by quibbling over items such as meal reimbursements.

African Americans make up a majority of the Democratic electorate in this early-primary state, and whoever wins them over next February will get an invaluable boost heading into other Southern state primaries the following month.

But as the candidates crisscross the state, some have exhibited a clumsiness and lack of sophistication that’s leaving black voters underwhelmed. This weekend could provide an early indication of whether Biden’s entry will clarify this landscape or muddy it.

As for Sanders, he could pay a price for neglecting to greet Pryce and her fellow volunteers. The 71-year-old managed Democratic Rep. James E. Clyburn’s first race for the U.S. House. She’s an author who has written about racism in Spartanburg housing policies. And a decade ago, in the same church kitchen, she had her first meaningful interaction with a politician named Barack Obama.

Sanders campaign aides say any slight was inadvertent; he didn’t eat anything at the event, they said, so he was unaware people had worked hard on the meal, and he spoke to as many people as he could. But now, for anyone in Pryce’s network who asks for her opinion of Sanders, she has a sour first impression to relate.

For the forgiving, such flubs reflect little more than inexperienced campaigns making the usual early missteps, and do not suggest a larger problem. Most of the Democratic hopefuls have not run a national race before, and their staffs are pinballing time-strapped candidates across South Carolina and other states.

But for others, the lack of attention to detail is a sign that the candidates’ concerns about black voters will evaporate after Election Day. That’s been a recurring complaint of African American leaders, and some worry that — for all Democrats’ emphasis this campaign on inclusion and diversity — the basic dynamic remains unchanged.

Anton Gunn, who was South Carolina political director for Obama’s 2008 presidential primary campaign, said he made sure that interpersonal connections were a cornerstone of Obama’s effort. In Southern states especially, black voters use unscripted interactions to draw conclusions about a politician’s character, he said.

And those impressions endure. “When we were running in 2008 against Hillary Clinton in the primary, I had older black women telling me they were loyal to Hillary because of something Bill Clinton had said to them in 1992,” Gunn said.

Many candidates enlist local officials to help them put on their best face. Not having those people, or not getting good advice from them, is a signal that campaigns “don’t have the institutional relationships with black communities and communities of color, and definitely don’t have relationships with communities in the South,” Gunn said.

He added, “I expect them to make mistakes. But the question is: Will they make the same mistakes over and over again?”

Harris is a member of the Alpha Kappa Alpha Sorority, a network of black women, many of whom say they’re ready and waiting to be mobilized on behalf of one of their own. Harris has spoken at several AKA events but has not tapped into this network in a significant way, members say.

When Harris spoke on the campus of Winthrop University in South Carolina recently, three AKAs helped count the crowd and ushered people to their seats. But the women had volunteered on their own, not because the campaign had approached them.

“That actually has been the line: ‘What can we do?’ ” said Sherell Fuller, an assistant professor at Winthrop and an AKA. “You want to support. Because I know people who are like, ‘I don’t really know that much, but she’s a sorority sister.’ ”

People close to the Harris campaign say they plan to make a formal outreach to AKA as the campaign unfolds.

On another occasion, a local Democratic Party volunteer dropped off a group of staffers for one of the presidential candidates at a lunch prepared by a personal chef following a slate of campaign events. Instead of allowing the volunteer to partake in the high-class meal, she was directed to a nearby fast-food restaurant.

“We have certain issues that we talk about — namely, can you treat somebody like your mama raised you right?” said the activist, who didn’t want to be identified for fear of alienating the campaigns. “Because we’re Southern, and that’s what we talk about. When you treat someone poorly, we talk about it.”

Sanders in particular has struggled to connect with the state’s African American voters, who constituted nearly two-thirds of South Carolina Democratic primary voters in 2016. That year, only 14 percent of black Democratic voters chose him, according to exit polls. His rallies in South Carolina earlier this year drew hundreds of people, but only a handful were African American, even when the events were held at black churches in black communities.

Still, the landscape is complex and fluid, especially at this stage of the campaign. The black vote is hardly a monolith and could split among several candidates, especially with so many to choose from this time. In addition, some of the pastors and politicians who have long been power brokers in the state are being challenged by a new generation of younger activists who are more apt to communicate in chat rooms than church halls.

African American voters, like other Democrats, are focused strongly on ousting President Trump, and some say privately they believe a white candidate would have a better chance of doing so. In 2008, many black voters remained wary of Obama until he won the Iowa caucuses, demonstrating decisively his ability to attract white voters.

Staffers for the Democratic campaigns say the candidates are beginning to forge connections and will continue to do so as the race evolves. Symone Sanders, who worked for Sanders in 2016 and is now a senior adviser to Biden’s campaign, said the former vice president’s ability to connect with voters is one of the reasons he leads several polls in South Carolina.

“You are asking people to sign up and saying that you understand their plight and you’re going to work to make it better,” said Symone Sanders, who is black. “They’re making a decision not just for themselves, [but] for their community. . . . If you want someone to put that kind of stake in you, there has to be some kind of relationship.”

Former Ohio state senator Nina Turner, one of the chairs of Sanders’s campaign, who attended the event at Mount Moriah Baptist Church, said Sanders is not the kind of person who would knowingly ignore those who worked hard to put on an event.

“He talked to everybody that he could,” said Turner, noting that Sanders was swarmed by elected officials and locals. “Certainly, had the senator known — I don’t think he knew that people were working diligently to make this event the best it could have been in terms of food — he would have gone back there.”

Her candidate is near the top of many polls and has wide name recognition, she said, and “people swarm him all the time, whether we’re at a formal event, a town hall or whether he’s just walking down the street. So, yes, he does make time.”

Pryce said that for her, the missed moment was about more than a few seconds of face time. She’s seen many politicians over the years, and she said Sanders missed an opportunity to learn from her decades of experience talking to and learning from South Carolinians.

“We could have pointed out some things to him,” she said. “He could have learned something.”

Chelsea Janes in Rock Hill, S.C., contributed to this report.