As another valuable contribution to the eternal debate over “polarization,” Emory’s Alan Abramowitz offered a reminder at WaPo’s Monkey Cage yesterday that sharp partisan and ideological differences among Americans aren’t just some artifice imposed on Americans by interest groups, the media, or party elites; they are rooted in powerful group identities of race and religion.

Contrary to the views of those who see polarization as almost entirely an elite phenomenon, the deep divide between the parties in Washington and in many state capitols is largely due to the fact that Democratic and Republican elected officials represent electoral coalitions that differ sharply in their social characteristics and political orientations. The roots of polarization are in our changing society—and above all the growing racial and ethnic diversity of the American population.

Racial/ethnic identification with one of the two parties is, of course, self-reinforcing; Republican perceptions of Democrats as the party of minorities strengthen the GOP’s own identity as the White People’s Party, and vice versa. But religion is a factor as well:

Race has certainly not been the only factor behind rising partisan polarization. Another crucial component of the ideological realignment of the past thirty years has been a growing religious divide between the parties. This is not the traditional divide between Protestants and Catholics that dominated American politics in much of the country during the first half of the 20th century. Instead, it is a divide between the religiously observant and non-observant.

While Alan’s numbers are impeccable, I do demur a bit from this last judgment. It’s true that all other things being equal, religiously observant Americans are more likely to vote Republican than non-observant Americans. But (a) race and ethnicity, and (b) religious beliefs, cut across that definition. Obviously enough, religiously observant African-Americans vote Democratic more than religiously non-observant African-Americans. I’ve seen some research (can’t conjure it up right this minute) indicating that observant white mainline Protestants vote Republican slightly more than non-observant white evangelicals, but overall mainliners definitely are more prone than evangelicals to vote Democratic. And among Catholics, the big divide may be interpreted as being between more and less observant communicants, or between those holding “traditional” or “modern” view of the Church and its teachings. These definitions overlap, but the content of religious belief, and the identity of believers, still matter a lot.

Ed Kilgore

Ed Kilgore is a political columnist for New York and managing editor at the Democratic Strategist website. He was a contributing writer at the Washington Monthly from January 2012 until November 2015, and was the principal contributor to the Political Animal blog.