“I keep going back to a lot of people telling me there’s no way I can win in my district, they thought I could never get elected to my seat,” she said. “Why is it more natural for a white man to be electable than an African-American woman?”

Ms. Breed is far from alone in wondering what Ms. Harris’s aborted run means for the political standing of black women in Democratic politics. The California senator’s decision to exit the race before the first round of voting has sparked an emotional reckoning, as the small sorority of prominent elected black female officials, strategists and candidates find themselves grappling with how Ms. Harris fell from a top contender to near the bottom of the pack, why she failed to attract black supporters and wondering what it will take for one of them to not only run, but also win, the White House.

For the first time in their political lives, many saw their own identity reflected in Ms. Harris’s bid, in the photos of her as a young girl in braids, her membership in the Alpha Kappa Alpha sorority, her stories of being bused into a white school district and her drum line dance moves.

They also saw in her effort a Democratic Party establishment unwilling to fully back their candidacies, even as black women remain the party’s most loyal supporters. And they saw confirmation of how much more difficult it can be for a black woman to raise money from people who like her but just aren’t convinced she should be — or could be elected — president.

Representative Barbara Lee, who represents Oakland, said the possibility of an all-white slate of top-tier candidates — and the likelihood of an entirely white roster at this month’s presidential debate — after Ms. Harris’s exit from the race demonstrates a lack of respect for black women at the highest levels.