ATLANTA — Chyna Hester knew what she was supposed to say.

The 20-year-old Spelman College student had just attended a “Black Women’s Breakfast” featuring Kamala Harris, the Democratic presidential candidate and the second black woman elected to the United States Senate . And speaker after speaker had explicitly argued that black women should support Ms. Harris and leap at the opportunity to elevate someone with their lived experience.

But after the event on Thursday, as Beyoncé’s “Brown Skin Girl” played in the background, Ms. Hester made a sheepish admission: Ms. Harris was not her preferred choice. There were policy reasons — Ms. Harris has not rolled out a proposal on student debt cancellation, which is Ms. Hester’s top issue. But there was also something else. Even at the historically black all-women’s college that Ms. Hester attends, supporting Ms. Harris was a particularly uncool thing to do.

“It’s hard, you know. On social media, there’s a different meme about her every day,” Ms. Hester said. “A lot of young people don’t support her.”

“Why aren’t black voters supporting the black presidential candidates?” is an overly simplistic question. Like all voting blocs, black voters have diverse priorities that crisscross the ideological spectrum, creating fault lines across regions, generations and economic class. But in interviews with more than two dozen black voters in Atlanta and across South Carolina, many articulated a particular disenchantment with the idea that racial representation equated to change, and that they should automatically back a candidate who looked like them.