Hoist a Glass, Democrats. Demographic Destiny Is Back.

(Bloomberg Opinion) -- Democrats took control of the House of Representatives in the midterm election this month by dominating the suburbs in every region of the country. That phenomenon has been amply analyzed since Nov. 6. Less remarked upon but just as important is the drubbing the Republican Party took in places with significant numbers of nonwhite voters.

In districts where the voting-age population is more than one-quarter nonwhite, Democrats won 15 Republican-held seats, or almost 40 percent of their 39-seat gain nationally. Of the 100 largest nonwhite districts, Republicans now hold only seven. Of the top 200, Democrats hold 154.

These figures were compiled by Mark Gersh of the National Committee for an Effective Congress, a consultant to the House Democratic Campaign Committee. His analysis highlights the Republicans’ long-term problems in House races as the nonwhite population continues to grow. Once these House seats switch parties, few are likely to switch back.

The phenomenon was amplified this year by the presence of President Donald Trump; nonwhite voters turned out to vote against his party in unusual numbers. Latinos appear to have voted in about the same proportion as they did in the 2016 presidential election, and went solidly for Democrats. Trump’s hostility to immigrants and members of minority groups clearly was a major factor.

The Democratic House wins in November included pickups of Republican seats in South Florida, Texas, New Mexico and California, most in districts with large nonwhite populations.

Even the few Republicans who won in these types of districts struggled more than expected. Will Hurd, who represents a huge slice of the southern Texas border, distanced himself from Trump on immigration, and election-eve polls showed him ahead by double digits. But he barely won, by about 1,000 votes, apparently because of a surge of Latino voters. Republicans expected an easy win by David Valadao, a pro-immigration lawmaker from California’s Central Valley; if he survives an extended vote count he’ll win by less than 1 percentage point.

The only secure Republican incumbent in a district with large numbers of nonwhites may be Mario Diaz-Balart, who represents Miami’s conservative Cuban-American community.

Even in a suburban Atlanta district centered in Gwinnett County, with a fast-growing minority population, the conservative Republican Representative Rob Woodall hung on by just 900 votes, and might have lost if not for the state’s efforts to discourage minority voters with roadblocks erected in the name of preventing (virtually nonexistent) voter fraud.

Minority voters made the difference for Democratic victors in two affluent Texas districts with long Republican traditions.

In Houston, a seat that Republicans held for more than half a century starting with George H.W. Bush went to Democrat Lizzie Fletcher over incumbent John Culberson, who foolishly embraced Trump. She won by five percentage points, attracting lots of college-educated women. But it was the nonwhite turnout, 25 percent to 30 percent of the total, that delivered her victory.

It was similar picture in north Dallas and its suburbs, where Colin Allred, an African-American lawyer and former professional football player, easily knocked off House Rules Committee Chairman Pete Sessions.

The biggest upset on election night was in Oklahoma City, where Democratic challenger Kendra Horn defeated Republican Representative Steve Russell; 15 percent to 20 percent of the vote was nonwhite. (Another decisive factor there was the $400,000 spent on Horn’s behalf by Michael R. Bloomberg, the owner of Bloomberg LP and a major supporter of Democratic candidates this year.)

Democrats have long expected to benefit from the demographic changes in the U.S. population, an assumption that grew stronger with the 2008 election and 2012 re-election of President Barack Obama. Trump’s 2016 victory, propelled by white voters, led many Democrats to challenge the notion that demography would become political destiny — or to acknowledge that the changes might be slower than they had anticipated.

Gersh, a hard-edged realist with an encyclopedic knowledge of congressional districts (he predicted a Democratic pickup of 38) thinks the turning point has now arrived, at least when it comes to House elections.

“As the United States turns more diverse,” Gersh said last week, “the current version of the Trump-Republican Party coalition is headed for extinction, or at the very least faces an insuperable disadvantage.”

This column does not necessarily reflect the opinion of the editorial board or Bloomberg LP and its owners.

Albert R. Hunt is a Bloomberg Opinion columnist covering politics and policy. He was the executive editor of Bloomberg News, before which he was a reporter, bureau chief and executive Washington editor at the Wall Street Journal.

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