Biden passed the torch to Harris. Now, how does he help her win?

Democrats succeeded in pressuring President Joe Biden to end his presidential campaign. Now, they're debating how best to utilize him to help Vice President Kamala Harris' bid for the White House.

Some want to see him out on the stump, both with Harris and by himself, as well as in ads and high-profile White House addresses. Others want to see him focus on governing, arguing that being the best president he can be is the greatest way to help after flubbing the race's highest-profile moment in last month's debate led to his electoral downfall.

The decision marks just one of several unprecedented factors for Democrats as they look to reinforce Harris' budding campaign, balancing establishing her as a candidate in her own right with her role as the No. 2 to an unpopular president who the party still credits with delivering a muscular record and making a "selfless" decision.

"That is a delicate balance, because this administration is far from over, and she's a part of that administration," said former Sen. Doug Jones, D-Ala., an ally of both Biden and Harris.

"She has got to step out and be her own person at this point and do it in a way that's sensitive to anything ongoing in the administration, but also with an eye toward not just the election, but her own administration," he added.

Some Democrats told ABC News the best way to do that is to blitz the campaign trail herself and leave Biden in the Oval Office.

Biden has at times shined on the stump, though he has consistently struggled in public, including at June's debate but also in media interviews and news conferences. Making that gamble again as Harris looks to get her candidacy off the ground with just about 100 days to Election Day isn't worth it, those Democrats argued.

"I don't think you need him out there making appearances," said one informal adviser to the campaign. "The reason he's not running is because he doesn't have the gas in the tank to do it."

Other Democrats weren't as blunt, but they did say that some physical distance between Biden and Harris during the campaign could offer the vice president a reprieve from poll numbers that had shown most voters trust Biden less than former President Donald Trump on key policy issues.

One source familiar with the Harris campaign's thinking said Biden would "probably" be better off in situations where he wouldn't be speaking live.

"I think it's important that she demonstrate that she has her own unique vision and agenda," the person said, though they added that, "I do think that there are ways that [Biden] could be used," including in ads.

One of those ways could be making progress on his own initiatives while in office -- and show that Harris is at his side.

"It's almost not on the campaign trail, but in the White House. What are they doing to showcase her, to give her leadership opportunities, to take full advantage of communicating to the country that she is, in fact, the vice president of the United States?" said Democratic donor and Harris supporter Steve Phillips.

"There's a power in cultivating and conveying images regarding the transfer of leadership within the Oval Office, within the White House, within this iconic building in our country."

Other Democrats said Harris' campaign should be less restrictive with how Biden is used and rejected the idea that there needs to be distance placed between the two of them.

Core administration policies, like raising taxes on the wealthy and protecting abortion rights, remain popular with voters. And several Democrats who spoke to ABC News said that they expect opinions of Biden will improve after dropping out of the race.

Bolstering that point, a New York Times/Siena College poll showed Thursday that his approval rating had ticked up to 41% from 34% earlier this month.

"I wonder now that he has passed the torch, does that make people view him more favorably and just recognize how powerful it is what he did," said one Democratic strategist close to Harris' team. "It may mean that people actually have better appreciation for what he's accomplished, what they've accomplished. And certainly, I think he is a great validator for the Biden-Harris record."

Rather than stay off the stump, some Democrats argued, Biden should instead hit the campaign trail as much as he likes.

His stops would likely generate massive media coverage, and he could offer a defense of his record -- and Harris' part in it -- while letting his vice president focus on the future of her own administration.

"When the president shows up in a community he dominates the media. So, the president can probably keep as much of a travel schedule as they feel comfortable," said Jamal Simmons, Harris' former communications director in the Biden administration. "He can tell the story of the Biden-Harris administration as well as anyone, and she can tell the story of what the Harris administration will do."

Those rallies could be held by himself or jointly with Harris -- "there's no reason for the vice president to shy away from him," Simmons said.

Logistically, Biden would likely be deployed in ways that could maximize his strengths and allow Harris to expand her voter base.

Democrats boasted that he could appeal to working-class voters, seniors and independents -- all demographics he performed well with in 2020 who would need to be kept in the fold as Harris regains ground with younger voters and voters of color who were drifting away from Biden.

"He can help in the Midwest, some of the blue-collar workers, some of the places where he's got a unique relationship to those voters with the 'Scranton Joe' kind of thing. And older voters love him," said the strategist with ties to Harris' team.

Biden also retains goodwill "among a lot of independents and even moderate Republicans who may have questioned his age but not his ability and his sincerity," Jones argued.

For his part, Biden has indicated he's ready to campaign for Harris. And while the campaign did not specify how he'll be deployed, spokesperson Lauren Hitt told ABC News in a statement the president will be "an effective advocate for the Vice President on the campaign trail."

"My expectation is that he will play whatever role the vice president asks him," said Mitch Landrieu, the former New Orleans mayor and Biden administration official.

"Everything and anything, any and all, repeat and rinse," Landrieu added when asked exactly what that looks like. "The president's going to be in it to win it for her."