Many Democrats have lamented how a party that believes in and champions diversity has managed to produce a top tier of presidential candidates that is white. Former housing and urban development secretary Julián Castro, who is Latino, exited the campaign last week. Sen. Kamala D. Harris (D-Calif.), who is African American, did so last month. And, once again, Sen. Cory Booker (D-N.J.), also black, will not be on the debate stage next week. Nor will former Massachusetts governor Deval Patrick. He, too, is African American. Andrew Yang, the New York entrepreneur who is Asian American, was the only person of color at last month’s debate. He didn’t qualify for next week’s debate.

But a new poll of African American voters from The Post and Ipsos gives me a chance to take Democrats by the lapels and shake some sense into them. The top tier of the Democratic field is white because black voters, generally speaking, want it that way.

Before you @ me, remember the truism: No candidate will win the Democratic presidential nomination without significant support from African Americans. They are the foundation of the party, and black women are its backbone. And the Post-Ipsos poll, like many national polls before it, makes it clear that they want Trump defeated and they think former vice president Joe Biden is the person to do it.

Biden snagged 48 percent of those surveyed when asked which candidate they would vote for or caucus for in their state. The next-closest was Sen. Bernie Sanders (I-Vt.), with 20 percent. Sen. Elizabeth Warren (D-Mass.) came in third with 9 percent.

Biden had the highest net approval rating among registered Democrats (69 percent) and overall (78 percent). Sanders followed with 63 percent and 71 percent, respectively. And Warren came in third with 51 percent and 58 percent, respectively.

Biden led on “best chance to defeat Trump” (53 percent), “handles issues important to blacks” (32 percent), “would unite the country” (43 percent), “strong character” (33 percent) and “closest on issues” (35 percent). Sanders is second to Biden on all these questions. But Warren comes in third on just “would unite country“ (6 percent), “strongest character” (10 percent) and “closest on issues” (9 percent). Interestingly, former New York mayor Mike Bloomberg did better with black voters on “best chance to defeat Trump” (6 percent) than Warren (5 percent). And Booker did better on “handle issues important to blacks” (14 percent) than Warren (7 percent).

The poll also shows that supporters of Biden, Sanders and Warren chose Biden, Sanders or Warren as their second choice. So, for African Americans in this survey, a white Democratic nominee is fine by them. But what about vice president? A bit of conventional wisdom that has taken hold is that if the nominee is white, then a person of color most certainly will have to be the vice presidential nominee. Harris and Stacey Abrams of Georgia, who lost her bid to be the first African American female governor in the nation in 2018, are the two names that folks mention every time. Surprisingly, the Post-Ipsos poll throws cold water on that thinking.

“If a white candidate wins the Democratic presidential nomination,” the poll question reads, “how important, if at all, would it be to you personally that the nominee choose a vice-presidential running mate who is black?” A whopping 72 percent said it was “less important,” including 38 percent who said it was “not at all important.” That’s more than the net 27 percent who said it was “fairly” important.

What this new Post-Ipsos poll of African Americans voters has done is confirm that my Aunt Gloria has her finger on the pulse of black America. At the family barbecue, I asked her why she thought Biden was the person to take on Trump. Her answer left me slack-jawed and remains the best explanation for Biden’s continued strength. “The way the system is set up now, there is so much racism that it’s going to have to be an old white person to go after an old white person,” Aunt Gloria said. “Old-school against old-school.”

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