President Joe Biden plans to launch a nationwide effort to mobilize Black voters during a campaign rally in Philadelphia on Wednesday, aiming to win back support from a slice of the electorate that polls show wavering in support.

Joined by Vice President Kamala Harris and a slate of Black elected officials, Biden is expected to boost his achievements while also warning of what his campaign calls a “racist and toxic agenda” being peddled by his rival, former President Donald Trump.

The launch of Black Voters for Biden-Harris, held at a majority-Black prep school in Philadelphia, is intended to revive another corner of the coalition that helped propel Biden to the White House in 2020. It’s his third stop for an event in the city this year; he held seven events in Philadelphia in 2023.

Biden’s aides say they aren’t taking Black voters for granted as surveys suggest an erosion of support, particularly among Black men.

“Our campaign believes that Black voters deserve to hear from Team Biden-Harris, and they deserve to have their vote earned, not assumed,” the campaign said ahead of the event, pointing to eight-figure investments in advertising, engagement efforts and “culturally competent content.”

“No campaign has valued Black voters like we have, including through investing earlier and with more money than ever before talking to Black voters,” the campaign said.

Still, the results of those efforts have proven elusive. Many polls have found Black voters more disconnected from the Democratic Party than they have been in decades.

A New York Times/Siena College survey of battleground states released this month found Trump winning more than 20% of Black voters in a two-way matchup with Biden, which would amount to a historic high if it translates to votes in November. Trump won roughly 1 in 10 Black voters nationally in 2020, according to multiple estimates, including 12% in CNN’s exit poll.

Perhaps more worrisome than a shift to Trump, according to some of Biden’s allies, is a fear that Black voters will sit the election out entirely.

Nowhere would that be more problematic than in Philadelphia, whose strong showing for Democrats in past elections — particularly among its Black population — has helped deliver Pennsylvania’s 19 electoral votes.

Biden has aggressively courted Black voters this month, including a multi-day stretch commemorating the historic Brown v. Board of Education case that found laws promoting segregation unconstitutional, campaign stops in Atlanta, a commencement address at Morehouse College and a speech at an NAACP dinner in Detroit.

He’s also dialed into Black radio programs and touted issues like infrastructure investments and canceling student debt when promoting his record to Black voters.

Following Wednesday’s rally in Philadelphia, Biden plans to deliver another set of remarks at a Black-owned small business, attended by members of the city’s Black Chamber of Commerce.

As the summer progresses, the Black Voters for Biden-Harris organizational effort will partner with community groups to register voters and strengthen voter protection efforts.

Key to the effort, the campaign says, will be engagement with networks of “trusted messengers” within Black communities and engagement events in battleground states — including at churches, block parties, barber shops and hair salons.

Trump has tried in his own way to court Black voters, even as the Republican Party shut down minority outreach centers in some battleground states. Sometimes his efforts have trafficked in stereotypes – at a gala in South Carolina earlier this year, Trump suggested Black voters like him more after his criminal charges.

“A lot of people said that that’s why the Black people like me because they have been hurt so badly and discriminated against, and they actually viewed me as I’m being discriminated against,” Trump said in February – comments that the White House and Biden campaign condemned.

And at a rally in Bronx last week, Trump sought to showcase his support among the Black community by posing with hip-hop artists

“While we are busy putting in the work to earn Black America’s support — Donald Trump continues to show just how ignorant he is,” said Biden principal deputy campaign manager Quentin Fulks. “Hosting janky rap concerns to hide the fact that he lacks the resources and competence to genuinely engage our community.”