Not surprisingly, the publication of the report has sparked considerable conversation, including in the political world, where Rush Limbaugh blamed President Obama for the recent shifts – as if the results were necessarily discouraging and in need of a culprit bearing responsibility – while Bill O’Reilly pointed the finger at “pernicious” entertainment he doesn’t like. (I tend to think the politicization of religion is itself, ironically, a key factor in the recent trends.)

But whatever the cause of the shifting religious landscape, the political and cultural impact is likely to be significant. The New York Times’ Nate Cohn explained, “Conservatives and Republicans, for example, have traditionally relied on big margins among white Christians to compensate for substantial deficits among nonwhite and secular voters.”

We tend to think of the GOP’s demographic problems as related to race: Republicans tend to rely heavily on white voters, which is a long-term problem in a country with increasing racial and ethnic diversity. But the religious demographics matter just as much: Christian conservatives are a key pillar of the GOP coalition. As the share of American Christian population falls, the pillars weaken.