Of course, complicating this theory is the fact that the only Democrat who’s won the presidency in the past 20 years is a black man—one whose winning coalition consisted of not just white working-class voters from rural areas, but also a lot more nonwhite voters in urban areas than Clinton received. Clinton lost Michigan by only 10,704 votes. Yes, she got pummeled by Trump in rural areas. But she also won some 70,000 fewer votes than Obama did in the heavily minority counties that include Detroit and Flint, just like what happened to her in Philadelphia, Pittsburgh, and Milwaukee. (She also lost in the suburbs.) Losing swing-state white voters to Trump certainly hurt Hillary—but losing those minority voters who didn’t turn out may have hurt her more.

Read: A warning to the Democratic Party about black voters

The importance of turning out minority voters in those states was on happy display for the Democrats during their blue wave of 2018. Michigan elected a 37-year-old African American man who’d never held elected office before as its lieutenant governor. Wisconsin elected a 33-year-old lieutenant governor, Mandela Barnes, whose presence on the ticket boosted black turnout in and around his old state-assembly district in Milwaukee, which in turn provided the narrow margin the Democratic ticket needed to defeat the incumbent governor, Scott Walker.

The problems presented by the absence of visible minority candidates in the Democratic primary go beyond motivating turnout; they affect what gets most talked about in the campaign.

The process the Democratic National Committee is using to winnow who gets to appear on the debate stage “seems to be selecting for the very things the Democratic Party is talking about trying to reduce: the outsized influence on our democracy of the wealthy to warp the rules for more of a stratification of wealth in our country,” Booker told me yesterday morning.

Aside from making it harder for the candidates who haven’t qualified to fundraise and get attention, the debates themselves have done nothing to significantly shape the race so far. Notably, television audiences have been nosediving—the last debate attracted only 6.5 million viewers, and expectations for the next one, to be broadcast on PBS on December 19, are low.

Still, many African American and Latino leaders are outraged about the likely composition of the December debate, charging that the DNC has fumbled by imposing debate-qualification rules that have hamstrung candidates who might have been able to assemble a winning coalition. An all-white debate stage might come off like a two-hour infomercial for minority voters about how the party doesn’t look like them.

Of course, the candidate who consistently polls the highest among minority voters has never been Harris or Booker or Castro. It’s Joe Biden. His campaign argues that this suggests he’ll have no trouble turning out minority voters.