When Biden campaign manager Greg Schultz traveled to New York in January to hold a campaign briefing with current and potential donors, one attendee told Schultz he believed black voters would only support Biden so long as they thought he was the winning candidate, according to two people with knowledge of the conversation.

“As soon as they don’t think you can win, they’ll go missing,” he warned.

Kenny Thompson, a former Biden aide who is helping raise money for his campaign, said Biden’s long track record with black communities has built up a resilient base.

"Speaking as a donor and former staffer and being black, I knew the vice president's resonance with black voters was real," Thompson said. "And I think a lot of that was from his work in the Senate, but also from having the back of Barack Obama for eight years. That goes a long way."

While some black donors have told Biden his position could be under threat, Buttigieg’s inability to break in with black voters so far has been a major warning sign about his campaign in the polls, and that has extended to the donor world.

Last week during a private breakfast at his New York headquarters, Buttigieg met with half a dozen black businessmen to discuss racial issues. The meeting was one in a series of quiet conversations that Buttigieg has held with black leaders over the last year, with his policies and relations in the black community under the microscope, especially in the months since a police officer shot and killed a black man in South Bend last June.

On NBC’s “Today” show Tuesday, Buttigieg said that voters of color who are “laser-focused on defeating this president” will be drawn to him after his Iowa victory. But in New York, he focused on pitching his “Douglass Plan” for improving race relations, as well as discussing his handling of the South Bend shooting.

Buttigieg’s plans are okay, two people at the meeting said — but his pitch lacked both a sense of urgency about dealing with race and a sense of empathy for the challenges that black people are facing.

“He has an almost unimaginable inability to connect with black people," said one person who was at the meeting. Buttigieg's campaign has hired several black fundraisers to help it raise money, including Marcus Switzer, a senior adviser for fundraising on the campaign.

Bernie Sanders has gained significant support from nonwhite voters this election compared to 2016, but neither Sanders nor Elizabeth Warren has been working to court support from black business leaders as they wage anti-corporate campaigns. Those largely moderate donors worry voters are not interested in the progressives’ platforms.

“Black donors are sophisticated and they want to see candidates engage on a full-scale level. Right now, if I’m being transparent, I don’t think any of the candidates running are up for the challenge,” said Quentin James, founder of The Collective PAC, which raises money for black candidates. “People are frustrated. I don’t know how else to communicate that.”

Their concerns will be tested on a broad scale in the upcoming contests in Nevada and South Carolina, where black and Latino voters will for the first time make up a significant portion of the electorate. Biden has consistently led with support from black voters in the race, gaining the support of 27 percent of black voters in a national poll conducted by Quinnipiac University this month, followed by Bloomberg with 22 percent of support and Sanders with 19 percent. Biden’s lead has declined recently as candidates including Sanders and Bloomberg have gained popularity.

Bloomberg and his team have been taking input from donors and activists as he drew up his policies for tackling racial inequality and tried to overcome the legacy of stop-and-frisk policing. Though Bloomberg is self-financing his campaign, he still courted donors on Tuesday on a call with the Black Economic Alliance, a donor circle whose members include pharmaceutical executive Tony Coles and Charles Phillips, who chairs the board at the cloud computing giant Infor.

“The fact is Amy Klobuchar, Buttigieg, [Elizabeth] Warren, and Sanders all do extremely poor with voters of color. And I don’t see that changing during this race,” said South Carolina state legislator Bakari Sellers, who helped raise money for Harris earlier in the presidential race. “There still is a theory that Joe Biden may be the best one, but you know, it’s tough.”

Sellers is one of a cadre of former Harris supporters who has passed on helping a candidate since she left the race. A number of black fundraisers who helped Booker have also decided to sit the primary out, at least for now.

“I support Kamala Harris for vice president,” Sellers said. “There are a lot of us that’ll come along if she supports someone.”