James Moore, a 62-year-old truck driver, said while he could vote for a black woman, he would prefer Mr. Booker or Mr. Biden, because he wondered if the country was ready to elect a black woman.
“Ms. Harris seems like a decent person,” Mr. Moore said, “but I just don’t think she’d have a chance, and I don’t want to throw away my vote.”
But nonwhite women — more than men — represent the core voting base of the Democratic primary and are arguably the most important constituency for any Democratic nominee. At Ms. Harris’s first two public appearances since announcing her candidacy, the Pink Ice Gala in South Carolina and her Oakland kickoff rally Sunday, black, Latina and Asian women turned out in droves to witness the launch of her candidacy.
Rozena Harten, of Oakland, said she did not believe Ms. Harris’s candidacy depended on black male support.
“I think black women are more involved,” Ms. Harten said. “I’m tired of men.”
Tiffany Stevenson, 44, also a member of the Alpha Kappa Alpha sorority, said she was “really energized” by Ms. Harris’s speech at the Oakland rally. “I think it shows the type of America I think America wants to become.”
In 2014, a research paper from the Center for American Progress, a liberal advocacy organization, argued that the main lesson from Mr. Obama’s victory in 2008 was that the Democratic Party needed to invest more in organizing and motivating nonwhite women, and specifically black women.
“As their numbers increase and their participation grows, women of color will increasingly have the chance to sway electoral results, influence which candidates run and win, and play a greater role in shaping the policy agenda,” the paper argued.
The author of that paper? Maya Harris, then a senior fellow at the organization.
Ms. Harris is now the chairwoman for her sister’s presidential campaign.