While we’re on the subject of the relationship between religion and social views, I’ve just received a pre-publication copy of a paper written by University of Southern Illinois sociology prof. Darren Sherkat and a couple of colleagues analyzing the connections between religion, partisan politics, and views of same-sex marriage. Yes, it”s a gnarly regression-analysis-laden exercise that will appear later this year in the journal Social Science Research–but it provides an excellent window into the structure of the culture wars in our time.

The paper looks at the two-decade period between 1988 and 2008, during which same-sex marriage went from being opposed by two-thirds of the American adult population to less than one-half. In 1988, opposition was more or less the same among Democrats and Republicans, and among the various species of Christians. Now there’s a substantial divergence between “sectarian Protestants” (evangelicals) and Republicans on the one hand and everyone else on the other. In a word, the sectarians and the Republicans have shifted far less towards acceptance of same-sex marriage than the rest of the population.

What Sherket et al.’s regressions show is that Republicanism as well as evangelicalism operate as independent variables: Both push their members toward opposition to same-sex marriage. (Just as, it seems, Democratic ideology pushes in the opposite direction.) Unfortunately, the researchers did not create an age cohort of voters born after 1978 that would enable us to see if sectarians in their 20s differed significantly from their elders. Be that as it may, the paper shows how a social issue that didn’t significantly divide the public on partisan lines two decades ago has come to do so. You don’t have to look further than this week’s vote on Don’t-Ask-Don’t-Tell to understand the dynamics.