Kamala Harris’s decision not to run for governor of California leaves open the door to a presidential campaign in 2028, even as her fellow Democrats are months into preparing for a future without her.

The ambitious governors, senators and former Biden administration officials who are already traveling the country, taping podcasts and building infrastructure for national campaigns have been aiming to put Ms. Harris and former President Joseph R. Biden Jr. in their collective rearview mirror.

And while Ms. Harris, as the former vice president, would enter the 2028 presidential primary as the most recognizable Democrat with the broadest fund-raising network, she would also carry the baggage of a 2024 campaign that Democrats do not view with much fondness.

At 60, she is certainly young enough to run again — and more than two decades younger than the president she served. But for a party seeking a reset after President Trump won for a second time, and figuring out how to win back trust with working-class voters, she would be anything but a fresh face.

More than a half-dozen people who spoke with Ms. Harris before she opted to skip the governor’s race advised against overinterpreting her decision as guiding her 2028 plans.

“I don’t think that any of us should jump to the conclusion that this decision had anything to do with 2028,” said Laphonza Butler, the former California senator who is close with Ms. Harris. “I do think that for her, all options are on the table if she wanted to go again and run for the presidency.”