Is Kamala Harris staging a 2028 comeback?

PHILADELPHIA—Democrats are ready to move on from 2024. But Kamala Harris isn’t done talking about it—as much as some in her party want her to be.

Her account of the campaign in her new book, “107 Days," is a more unvarnished look from the typically cautious former vice president than even those close to her were expecting. The candor hasn’t just reopened wounds for a divided party still struggling to chart a path forward. It has also left Democrats trying to discern Harris’s intent: Is the book the start of an unconventional political comeback, or a no-holds-barred exit from politics?

In a Wall Street Journal interview, Harris insisted it was neither. “This is a book tour," she responded. “That’s what it is."

Minutes earlier, Harris was standing in front of a packed opera house in the same city where she ended her campaign. Repeatedly audience members and the moderator encouraged her to run for the White House again, as the crowd cheered.

Harris has declined to rule out another presidential bid. Asked in the interview if she had a timeline for making a decision on her political future, Harris said, “You’re assuming I’m thinking about it," and wouldn’t elaborate.

The former vice president said she still views herself as a leader within the party. “I was the Democratic nominee for president," she said. “I came close to winning. Of course I do."

T-shirts from Harris’s 2024 campaign were worn at the former vice president’s book event.

Some longtime backers have privately said they are ready to move on. A vocal group of Democrats from across the party have aired their frustrations with Harris’s re-emergence and her book, in which she speaks bruisingly about former President Joe Biden and her choices for a running mate. She characterizes Pennsylvania Gov. Josh Shapiro as overly ambitious and former Transportation Secretary Pete Buttigieg, who is gay, as a politically risky pick alongside a Black woman.

Ashley Etienne, Harris’s communications director in 2021, said she sees the former vice president’s book as a missed opportunity because it doesn’t focus on the Biden administration’s accomplishments and her role in them as the first female vice president.

“I would have advised her to write a different book, one that cements her legacy," Etienne said.

A story told with clarity of purpose, Etienne said, “would be powerful in this moment and a beautiful contrast to what we’re seeing coming out of the White House right now."

Faiz Shakir, who ran Bernie Sanders’s 2020 presidential campaign, said Harris’s book and tour are a reminder of the concern people had about her. “Her campaign struggled with being a campaign of conviction, of clarity, of deep, principled positions," Shakir said.

“It’s a sign of weak leadership to just start blaming these kind of outside actors for your own shortcomings," he said. “It hurts the Democratic Party."

Sonali Sareen, 17, took a selfie with her mother, Priya Sareen, at the book event Thursday.

In the interview—which took place after her book event and before Harris boarded an Amtrak train from Philadelphia—she acknowledged the frankness of her book, but said she believes the critics who have focused on a few excerpts have missed her point. “It’s not a tell-all," she said. “It’s about just presenting people with a journal of my experience running for president of the United States."

Democrats, including some who have previously supported Harris, have said the former vice president’s instinct to straddle moderate and progressive policy positions instead of strongly articulating one side—even on the book tour—has made them uneasy about a potential comeback.

Harris was asked in an MSNBC interview with Rachel Maddow about Zohran Mamdani, the Democratic nominee for New York City mayor, whose democratic socialist candidacy has divided the party. “I support the Democrat in the race, sure," Harris said, without saying his name. Her response angered both progressives and centrists in the party. Progressives viewed it as a half-endorsement, and centrists thought her comment was too supportive. Harris later said she spoke to Mamdani on the phone and complimented him on bringing people together.

In the Journal interview, Harris was definitive. “No, I did endorse Mamdani," she said. Despite the growing divisions within the two wings of her party, Harris said, “There is a lot of consensus around the priorities of this moment, and that’s where I’m focused."

Over the summer, Harris passed on a run for California governor because she wasn’t ready to make a decision yet on a 2028 presidential campaign, and a gubernatorial bid would have probably meant passing on another run for the White House, according to people familiar with her thinking. There was a concern that she could become a distraction for Democrats and that supporters of President Trump could turn their focus on her, a person briefed on the matter said. She also didn’t feel ready for another campaign so soon after a bruising presidential election.

Harris stayed largely out of the public eye after her loss, as she tried to find her way.

She signed with a top Hollywood talent agency, Creative Artists Agency, in February to represent her in speaking and publishing engagements; CAA previously represented her. Harris’s team has asked for $250,000 a speech, according to people familiar with the discussions, and interest has so far has been limited. With U.S. companies concerned about retribution from Trump, lucrative paid speeches have been challenging to get for top Democrats and even some Republicans.

The biggest liability for Harris on the national stage remains her former boss and his ability to perform his presidential duties when he was in office, according to Democrats. Already, potential 2028 Democratic contenders have raised the topic.

In her book, she acknowledges that Biden “got tired," but added, “I don’t believe it was incapacity. If I believed that, I would have said so. As loyal as I am to President Biden, I am more loyal to my country."

A slideshow of 2024 campaign photos at the ‘107 Days’ event.

She is sharply critical of Biden’s team, and at times his actions, during her campaign after she declined to distance herself from him in 2024. She describes his decision to seek re-election as “reckless" and offers an overall candid assessment of their strained relationship: “My feelings for him were grounded in warmth and loyalty, but they had been complicated over time with hurt and disappointment," she writes.

Though Harris spoke to the former president before the first excerpts of her book were released, former Biden staffers have said they have been taken aback and confused by the level of detail Harris decided to include about her relationship with Biden. Many are furious at the amount of blame she pins on Biden and his advisers. A spokeswoman for Biden declined to comment.

Matt Bennett, co-founder of the Third Way, a center-left think tank, said Harris’s “willingness to be clear about what happened" is an important piece of the reckoning for the party. Bennett added: “I think what she has recognized is authenticity has become the coin of the realm in politics."

While addressing her supporters in Philadelphia, Harris said she hoped her book would give her party permission to have difficult conversations. She said Democrats need to start breaking some conventional political rules to start winning again. “We need to fight fire with fire," she said.

Write to Tarini Parti at tarini.parti@wsj.com and Emily Glazer at Emily.Glazer@wsj.com