Joe Biden says he won’t step aside. But if he does, here’s why Kamala Harris is the favorite to replace him.

WASHINGTON — President Joe Biden insists that only “the Lord Almighty” can convince him to quit the presidential race. But should he change his mind, Vice President Kamala Harris is by far the best positioned to replace him.

Harris would have a head start over several of the most discussed Democratic alternatives like California Gov. Gavin Newsom and Michigan Gov. Gretchen Whitmer. She’s already been on a winning presidential ticket with Biden, has years of goodwill banked with core party constituencies and would likely control a huge campaign fund amassed by the Biden reelection.

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Here's a closer look at her prospects in a potential open primary:

The president easily locked up the Democratic nomination and party rules prevent him from simply transferring the delegates he amassed during next month’s Democratic National Convention. But a number of delegates have already suggested they’d be loyal to Harris.

Biden picking Harris could limit potential chaos and avoid floor fights that do lasting damage to whoever emerges to take on Republican Donald Trump.

“Harris makes the most sense to carry on the Biden legacy,” said Andrew Feldman, a Democratic strategist who works closely with various state parties and stressed that the question was purely hypothetical since Biden insists he won't bow out.

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Feldman added that the Biden administration's agenda “has been tremendously popular in terms of the issues that they’ve championed” and that the president and Harris have "been doing that in partnership."

Antjuan Seawright, a South Carolina-based Democratic strategist, noted that voters four years ago put 78-year-old Biden in the Oval Office knowing Harris was next in line, and that Biden warded off primary challengers this year at age 81 with Democratic voters knowing Harris remained his second-in-command.

“Democrats have voted for Joe Biden with Kamala Harris,” Seawright said.

Harris is the first woman to serve as vice president as well as the first Black woman and person of South Asian descent. African Americans are Democrats’ largest and most loyal bloc of supporters.

Bypassing a historic No. 2 for anyone else — even a popular alternative from a key swing state — would already be difficult. Being seen as leading the charge against someone who broke gender and racial barriers could forever mark the challenger as disloyal in future Democratic primaries.

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Glynda Carr, who leads the Higher Heights political action committee which supports Black female candidates across the country, said that public suggestions that Harris could be bypassed for another top Democrat in Biden's absence shows "just how much Black women are oftentimes overlooked.”

“You want Black women to organize our houses, our blocks, our churches, our sororities?" Carr asked. "Then we’ve got to stand by our leadership.”

Democratic Rep. Jasmine Crockett of Texas said it is “impossible to understate” what it means for Black women to see Harris hold national office.

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Since Biden’s disastrous debate, Democrats have mentioned a parade of top alternatives who could run in the president’s place. In addition to Whitmer and Newsom, Pennsylvania Gov. Josh Shapiro and Illinois Gov. J. B. Pritzker have been the subject of rumors. All of them have said they’ll continue to back Biden.

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But, in dozens of interviews, Democratic operatives, pollsters and elected officials report that there has not been the kind of furious political jockeying for support for someone other than Harris at the convention that would be necessary if Biden were to step aside. Any such discussions have occurred quietly and preliminarily and would almost certainly be forced out in the open if Biden were to leave the race, making continuing them more difficult.

“Everyone would rather be a starter than a pinch hitter,” Feldman said.

For instance, Democratic fundraising bundler Barry Goodman, a Michigan attorney who was a finance co-chairman for both of Whitmer’s statewide campaigns, said he did not know of any coordinated effort on the governor's part to rally support.

Further possibly helping to smooth a switch from Biden to Harris is campaign finances. The vice president, as his official running mate, can access the $91 million cash on hand the president's campaign has raised — which grows to $240 million when including allied Democratic organizations — in ways Democratic alternatives likely can't.

For his part, Trump is already attempting to energize donors with the idea that Democrats could swap out Biden for Harris. The former president sent fundraising emails Monday titled “Biden’s dropping out” and “President Kamala Harris?”

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At 59, the vice president is 22 years Biden’s junior. A former prosecutor, she can deliver a withering attack in a debate — as Biden himself once faced during the 2020 Democratic presidential primary when Harris tore into him over his onetime opposition to school busing as a means of desegregation.

The vice president’s legal background might also hew more closely to the ideals of today’s Democratic Party, which has largely moved to the center on criminal justice and law-and-order messaging in recent years after nationwide protests against racial injustice in 2020 helped energize the “defund the police” movement.

Biden has seen his approval rating fall sharply among Black Americans, a trend Harris would hope to reverse before November. Still, Biden has long struggled with low approval ratings among Americans more generally and the vice president doesn't fare much better.

About 39% of U.S. adults have a very or somewhat favorable opinion of the vice president, which is in line with Biden's 40% favorability. But an AP-NORC Center for Public Affairs Research poll conducted in June found that slightly fewer have an unfavorable view of Harris, 49% compared to Biden's 57%.

Harris has a 62% favorability among Black Americans compared to 37% for Hispanic Americans and 35% for white Americans. Those are all similar to Biden’s, though there could be more opportunity for her to shape opinions. Roughly 12% of U.S. adults said they aren’t familiar enough with Harris to give an opinion, whereas nearly everyone has an opinion of Biden.