Harris, After a Debate Success, Confronts a Battleground ‘Game of Inches’

Her campaign is riding high, but still sees the race as an exceedingly close grind. Her aides have new hopes of focusing the race squarely on Donald Trump’s fitness for office.

Follow along with live updates on the Trump and Harris campaigns.

Vice President Kamala Harris’s strong debate performance has sent her campaign surging into the final weeks of the race with newfound confidence, sharper ideas about how to persuade the country that former President Donald J. Trump is unfit for office, and a host of questions about what comes next.

The Tuesday clash had long stood out as the final tent-pole moment for Ms. Harris on the campaign calendar, with the vice-presidential candidates set to face off on Oct. 1. Now, her team is fully open to a second debate with Mr. Trump, though he appears noncommittal.

While Ms. Harris’s top aides are thrilled with her debate showing and Mr. Trump’s inability to push consistent and coherent attacks, they are looking to tweak their strategy only around the edges. The next steps, close advisers say, are ramping up her visibility on the campaign trail, including retail politicking in communities, increased press appearances, and putting herself in front of as many voters as possible in battleground states. Aides believe that at its heart, the race is unchanged.

But Ms. Harris remains a key part of an unpopular incumbent administration in a nation where many voters say they want a decisive change and have expressed unhappiness with President Biden’s leadership.

Her quandary was encapsulated in the debate’s very first question, when Ms. Harris was asked if she thought Americans were better off now than they were four years ago. Instead of giving a direct answer, she talked about her middle-class upbringing and her plans to help working families. It was almost as if she felt it would be unwise either to embrace Mr. Biden too closely or to obviously distance herself from him.

The ultimate challenge for the Harris campaign dating to when it was Mr. Biden’s operation is less about moving Mr. Trump’s numbers — which have barely budged since 2016 — than it is about lifting hers. The bet her team is making is that some key voters who are leery of both candidates will back Ms. Harris if she can disqualify Mr. Trump in their minds.

Polls show that Mr. Trump retains a high floor of Republican support. Surveys in the battleground states show vanishingly tight contests. And while Mr. Trump’s campaign apparatus is a shell of what Ms. Harris and Democrats have built, a constellation of right-wing outside groups is investing millions of dollars in advertising, direct mail and organizers in an effort to overcome the vice president.

“This is a game of inches in the swing states,” Gov. Gavin Newsom of California said in the debate’s spin room on Tuesday night. “You’ve got to attach yourself to 20, 30, 40,000 voters in these key swing districts, the swing states. I mean, it’s not even about swing states. It’s about 30 or 40 counties within those swing states.”

Ms. Harris is heading on Thursday to North Carolina and on Friday to Pennsylvania, in a planned swing through battleground states that her campaign insists will not serve as a debate victory lap. Her rally on Friday in Wilkes-Barre, Pa., will be the sixth day out of seven she has had a public appearance in the state, the latest indicator of Pennsylvania’s importance to her path to 270 electoral votes.

She is also planning to sit for local media interviews in battleground states, according to a memo released Thursday by the Harris campaign, and will participate in an interview next week with the National Association of Black Journalists.

Officials with Ms. Harris’s campaign believe the debate helped her do something that Mr. Biden and his team long tried to make happen but could not because of his age and fading political dexterity: make the 2024 election about Mr. Trump.

The Biden campaign spent more than a year trying to do that, going so far as to successfully push to hold the first general-election debate in early summer so that Americans would fully grasp that Mr. Trump could indeed return to power. The campaign’s Thursday memo said it would release a series of advertisements featuring footage from the debate.

Now Mr. Biden is gone from the ticket, and Democrats have moved on from their summer of upheaval. With Ms. Harris having spent the 90-minute debate successfully baiting Mr. Trump into self-inflicted harm, her team hopes to spend much of the final eight weeks of the campaign drawing attention to his policies and his fitness for office.

“She made a stark case that rattled him,” said Gov. Roy Cooper of North Carolina, a longtime Harris ally. “It should tell the American people that this guy shouldn’t be president again.”

The first salvo in the Harris campaign’s post-debate effort to provoke Mr. Trump and place him in the national spotlight came as the vice president exited the stage. “That was fun,” Brian Fallon, one of her senior aides, wrote on social media, adding a challenge: “Let’s do it again in October.”

When the frustrated former president went to the spin room an hour later, he said he must have won the debate because only a loser would demand a rematch. By Wednesday morning, he told Fox News that if the network hosted a debate, its lead political anchors could not be fair to him, either — and that he would now prefer Fox’s prime-time opinion hosts to moderate.

“Let’s give other people a shot,” he said.

Gleeful provocations aside, the Harris campaign acknowledged after the debate that a hard road lay ahead. “Donald Trump rehashed the same old tired playbook,” read a fund-raising email addressed from Ms. Harris. “I refused to let him off the hook. But debates do not win elections.”

One challenge is that even though Ms. Harris has served for over three years as vice president, her record remains largely unknown to many voters.

That gives her an opportunity to win over new supporters, but also offers Mr. Trump a chance to negatively define her. And less than two months before Election Day, with several states starting to cast early ballots soon, far more people have made up their minds about Mr. Trump than Ms. Harris.

A New York Times/Siena College poll conducted this month showed that only 12 percent of voters said they needed to learn more about Mr. Trump, while 31 percent said the same about Ms. Harris.

Senator Laphonza Butler of California, a top Harris ally, said that some wavering voters could not “imagine beyond their traditional experience at this level of politics.”

“‘I need to know more’ is also an expression of some fear and hesitancy about something they’ve never seen before,” Ms. Butler said. “It’s the first time that a Black woman, a woman that has had the life journey that the vice president has had, has been in a position to run for the highest office in the land. And rather than to say, ‘I’m a little hesitant,’ maybe a better way, a more thoughtful way to express that, is: ‘I might need to know more. I don’t know enough.’”

Cornell Belcher, a Democratic pollster and strategist, said the Harris campaign would be wise to harness the energy of the burst of online memes mocking some of Mr. Trump’s outlandish assertions at the debate, including his false claim that immigrants were stealing and eating people’s pets in an Ohio town.

“It’s a cultural moment,” Mr. Belcher said. “That’s how most Americans make sense of their lives. It’s not through your five-point economic plan or your 12-point foreign policy plan. It’s the cultural stuff.”