The release of district-by-district 2010 census data last week marked a milestone: For the first time, minorities represented at least 30 percent of the population in a majority of the 435 House districts. The results underscore the relentless advance of what National Journal has called "the march of diversity" — the seemingly inexorable growth and diffusion of the United States' burgeoning minority population. One big message is that diversity is no longer a phenomenon in just the Sunbelt or major metropolitan areas; it is creating new political dynamics for legislators in virtually every state.

The hard population count in the 2010 data reinforced the trends that appeared in the analysis of the American Community Survey, the Census Bureau's annual poll that tracks population changes between the decennial counts. When National Journal first examined data from the 2006-08 survey, minorities represented at least 30 percent of the population in 205 House districts; data from the 2009 study showed that the number of such highly diverse districts had risen to 217. (See "Diversity Marches On" NJ, 1/15/11, p. 34.) The 2010 data show that minorities constitute at least that much of the population in 222 districts, an absolute majority.

National Journal

The redistricting process that follows the census may alter these numbers somewhat by either concentrating or dispersing minority communities. But even the most creative mapmaking won't reverse the trend.

Through a longer lens, the change is even more striking. In 1992, minorities represented at least 30 percent of the population in only 109 House districts, fewer than half as many as they do now. Conversely, over that same period, the share of House districts where whites represent at least 80 percent of the population fell by almost exactly half — from 245 in 1992 to just 122 in 2010.

In all, 34 states have districts with at least 30 percent minority populations — not only traditional immigrant destinations such as California (where 50 of the 53 districts are in this category) and Texas (30 of 32) but also Connecticut, Minnesota, and Oklahoma. Legislators representing "high minority" districts cross the ideological spectrum: Reps. Steve Israel, D-N.Y., and Pete Sessions, R-Texas, the chairmen of their parties' House campaign committees, each hail from a "high-minority" district. Eighteen House Republicans now represent districts in which minorities constitute a majority of the population.

The principal engine for this transformation is the swelling Hispanic community, which accounted for more than half of all U.S. population growth during the past decade. The 2006-08 census data found that Hispanics represented at least 20 percent of the population in 99 districts; in the 2010 results, that number spiked to 118. "The Latino influence on U.S. electoral politics used to be the exception," said Rep. Xavier Becerra, D-Calif. "It's now the rule."

Generally, the growing minority influence has benefited Democrats. But in the 2010 election, Republicans made substantial gains in districts where minorities represent between 30 and 40 percent of the population, partly because nonwhite turnout sagged more than usual after the 2008 presidential race.

The result was a stark divergence in the racial allocation of House seats. Republicans now control 156, or three-fourths, of the 213 districts in which minorities constitute less than 30 percent of the population. Democrats represent 89, more than four-fifths, of the 107 districts in which minorities represent a majority of the population. The disputed terrain in between now tilts toward the GOP: Republicans hold 68 of the 115 districts in which minorities constitute between 30 and 50 percent of the population. Democrats will inevitably target many of those seats in 2012, when President Obama's campaign will be working hard to expand minority turnout.

The same trends are evident when looking solely at the Hispanic population. Democrats hold nearly 70 percent of the 64 districts in which Hispanics represent 30 percent or more of residents. But Republicans hold 29 of 54 districts that are between 20 and 30 percent Latino, and the GOP maintains an edge at each level of Latinos' population share under that. That's partly because Hispanics, for a variety of reasons, haven't fully translated their growing numbers in the population into commensurate clout in the electorate. "We have to remember that because of youthfulness and rates of noncitizenship among adults, those numbers don't translate into significant numbers of voters yet," said Arturo Vargas, executive director of the National Association of Latino Elected and Appointed Officials. "But that's going to change."

As that ratio evolves, the pressure will rise on Republicans to replicate the success of George W. Bush, who attracted approximately 40 percent of Hispanic voters in 2004, according to exit polls. Republicans have long hoped to find common ground with Latinos on social issues, entrepreneurship, and national security. But some conservative Hispanics fear that the Republican Party is undercutting those potential areas of agreement by solidifying its opposition to any immigration reform that includes a pathway to citizenship for those in the U.S. illegally.

Mario H. Lopez, president of the right-leaning Hispanic Leadership Fund, worries that the GOP could alienate Hispanics the same way resistance to an earlier generation of immigrants cemented Irish loyalty to the Democratic Party for decades. "It's the same old story," he says. "If you don't learn from history, you're doomed to repeat mistakes." All the demographic trends suggest that avoiding those mistakes will grow increasingly important if Republicans hope to defend their House majority in the decade ahead.

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