It was a chance for Joe Biden to connect with a key group of voters who helped him clinch the Democratic presidential nomination and are crucial to his chances in November: an appearance on “The Breakfast Club,” a radio show popular with black audiences.

Instead, Biden’s suggestion that African Americans who are considering voting for President Trump “ain’t black” quickly overshadowed the rest of his interview, ricocheting across social media, drawing fire from black Democrats and culminating with the candidate rushing to express regret for his comments.

“I was much too cavalier. I know that the comments have come off like I was taking the African American vote for granted. But nothing could be further from the truth,” Biden said later in the day, during a virtual appearance with the U.S. Black Chambers, an organization that advocates for black entrepreneurs. “I shouldn’t have been such a wise guy.”

But the episode offered an uncomfortable reminder that while the presumptive Democratic nominee leads Trump in the polls and has long performed especially well among African Americans, his relationship with this core constituency still faces tests.

Many African American activists argued that while black voters powered Biden to victory in a competitive primary race, he needs to ensure that the community stays energized for November. And even some Biden backers said they worried that this episode would damage the former vice president’s standing.

“It almost came across as if black people need Joe Biden more than Joe Biden needs black people,” said Angela Rye, a former executive director for the Congressional Black Caucus and a leading Democratic activist. “This is a party that we’ve dedicated our votes and our lives to, and we are tired of being taken for granted, treated as invisible or being silenced.”

The Trump campaign immediately seized on the comments to try to drive a wedge between Biden and his voting base. By Friday afternoon, the campaign was selling T-shirts that read “#YouAintBlack - Joe Biden.”

Trump has a history of racist comments and has long struggled with black voters. But he is hoping to improve his margins in 2020, particularly in swing states like Pennsylvania and Michigan.

His campaign plans to open field offices in majority-black cities and has encouraged African Americans to sign up for Trump updates by texting the word “woke” to a campaign number.

Friday’s exchange occurred during a contentious interview with radio host Charlamagne Tha God, who pushed Biden on his record. When a Biden aide signaled it was time for the candidate to wrap up, Charlamagne said, “You can’t do that to black media.” He then told Biden he needed to come back on the show before November because there were more questions for him.

“You got more questions, but I’ll tell you, if you have a problem figuring out whether you’re for me or Trump, then you ain’t black,” Biden said.

“It don’t have nothing to do with Trump, it has to do with the fact — I want something for my community,” Charlamagne said.

In an interview with The Washington Post on Friday afternoon, Charlamagne said Biden needs to work to win over black voters. “The older black voters know the Joe in the Senate that has assisted black people and has been there for black people,” he said. “But we know ’94 crime bill Joe. We know ’86 crack laws Joe. We know ’84 mandatory-minimum sentences Joe. That’s what I’ve come to learn. So he has to win us over.”

 Within hours, Biden said he regretted the comments. “No one, no one should have to vote for any party based on their race or religion or background,” he said on the call with the U.S. Black Chambers. “There are African Americans who think Trump is worth voting for. . . . I’m prepared to put my record against his, that was the bottom line.”

Biden had not planned on personally calling in to the U.S. Black Chambers event — a staff member was going to be on the call, according to a person familiar with the event. But amid the backlash to his comments, the candidate decided to join so he could explain what he meant.

Biden’s team is counting on bringing black voters — particularly men — who supported Trump back to the Democratic Party. Last week during a strategy briefing, the campaign showed a slide outlining how “the Biden coalition will draw from key voting blocs,” such as African American men, which were referred to as “disaffected voters.”

Then came Friday’s comment.

“Here’s the problem with the statement and how it’s catching fire on social media: Those disaffected voters that I have been talking about and they are now paying attention to, a statement like this reinforced for them that in fact Democrats do take them for granted,” said Cornell Belcher, a Democratic pollster who worked on the Obama campaign.

The Biden campaign “cannot just depend on Trump simply being a racist to energize and move these disaffected voters,” Belcher said. “They are going to have to engage them with an issue agenda that speaks to their issues and resonates with their values. And that is where Biden should stay.”

A Fox News poll released Thursday found Biden leading Trump, 76 percent to 12 percent, among black voters. Hillary Clinton won about 90 percent of black voters in 2016.

In January, before Biden largely sewed up the nomination, a Washington Post-Ipsos poll of black registered voters found that 69 percent had a favorable view of Biden, while 13 percent held an unfavorable opinion. In a matchup with Trump, 82 percent of black voters supported Biden, while 4 percent backed the president.

During the Democratic primary contest, Biden stumbled with black voters several times. He struggled to defend his opposition to busing and his close relations with segregationist senators like Strom Thurmond (R-S.C.), whom he eulogized in 2003, and James O. Eastland (D-Miss.).

He also drew fire over the 1994 crime bill, which critics say led to the mass incarceration of blacks. Biden defended the legislation on the campaign trail but said he never supported the “three strikes” provision that sent many to prison.

But Biden seemed to move past those challenges thanks to support from key black lawmakers like Rep. James E. Clyburn (D-S.C.), whose endorsement days before the South Carolina primary helped deliver the state to him — a decisive victory that prompted other rivals to leave the race and line up behind him.

Biden has said that his Cabinet would be diverse, that he would appoint a black woman the Supreme Court and that he’s considering several black women as potential running mates.

But his comments Friday highlighted an underlying disconnect between him and black voters, adding more pressure to select an African American vice president.

“African American voters picked Joe Biden to be the Democratic nominee for many of these same reasons that Barack Obama picked Biden to be vice president — because he was the person who they thought would resonate with a part of the electorate that most black candidates don’t,” said Jamal Simmons, a black Democratic strategist who has a show on Instagram. “African Americans know the dark side of American culture better than most white Americans do.”

Simmons added that Biden “can be a little tone deaf” on race.

Even his relationship with Obama was not without turbulence. During the 2008 primary contest, Biden called Obama “the first mainstream African American who is articulate and bright and clean and a nice-looking guy.”

Biden’s campaign quickly got together a conference call for him to walk it back. “I really regret some have taken totally out of context my use of the word ‘clean,’ ” he said.

But many Biden supporters defended their candidate Friday, saying his inartful comment pales in comparison with Trump’s record.

“I would have said it differently,” said Antjuan Seawright, a Democratic strategist based in South Carolina who has worked closely with Clyburn. “I think the point he was trying to make is that at the end of the day, the agenda of Donald Trump and the Republican Party versus the agenda for the African American community that Joe Biden has put forth is night and day.”

Other Biden supporters pointed to Trump’s long history of incendiary comments directed at minority communities, including African Americans. During his presidency, he’s referred to some African nations as “shithole countries,” suggested that four congresswomen of color “go back” to where they came from and attacked the district of late congressman Elijah E. Cummings (D-Md.) in Baltimore as a “rat and rodent infested mess.”

“Trump is super racist. His campaign & his appeal is built on the perpetuation of white supremacy & white privilege. He stokes white fragility. When a Black person supports him I question their relationship to their Blackness and the community. This is what Biden was alluding to,” tweeted Touré, a black writer and commentator.

Matt Viser and Scott Clement contributed to this report.