If Democrats had stemmed the defections of white voters to the Libertarian or Green Parties, they would have won Michigan and Wisconsin, and had they also inspired African-Americans in Pennsylvania, Mrs. Clinton would be president.

If progressive whites are defecting because they are uninspired by Democrats, moving further to the right will only deepen their disillusionment. But if the next D.N.C. chairman can win them back, the country’s demographic trends will tilt the field in Democrats’ favor. As Mrs. Clinton’s popular vote margin showed, there is still a new American majority made up of a meaningful minority of whites and an overwhelming majority of minorities. Not only is there little evidence that Democrats can do significantly better with those white working-class voters who are susceptible to messages laced with racism and sexism, but that sector of the electorate will continue to shrink in the coming years. Nearly half of all Democratic votes (46 percent) were not white in 2016, and over the next four years, 10 million more people of color will be added to the population, as compared with just 1.5 million whites.

Keith Ellison, a D.N.C. chairman candidate, has a proven record of engaging core Democratic voters rather than chasing the elusive conservative whites, and the party would be in good hands under his stewardship. (Thomas E. Perez, the former labor secretary, has less electoral history, but his reliance on political superstars such as the strategist Emmy Ruiz, who delivered victories for Democrats in Nevada and Colorado, is encouraging.)

Whoever prevails as chairman must resist the pressure to follow an uninformed and ill-fated quest for winning over conservative white working-class voters in the Midwest. The solution for Democrats is not to chase Trump defectors. The path to victory involves reinspiring those whites who drifted to third-party candidates and then focusing on the ample opportunities in the Southwest and the South.

Mrs. Clinton came closer to winning Texas than she did Iowa. She fared better in Arizona, Georgia and Florida than she did in the traditional battleground state of Ohio. The electoral action for Democrats may have once been in the Rust Belt, but it’s now moving west and south.