The Pew Forum on Religion & Public Life released a new report on the increasing numbers of people who don't identify with any religion, and while the headline is that the number of such people has maintained its steady growth—now up to 20 percent of the population, and concentrated more heavily among younger adults—there's something else notable, about the political affiliations of this group.
Some people have pointed out that only some of these "nones" will actually say they're atheist, while many define themselves as "spiritual but not religious," which could mean anything and nothing, from "I believe in God but organized religion is corrupt, to "I get a profound sense of our interconnectedness when I look up at the stars." We also shouldn't forget that there are many people who continue to identify with a religion but are actually non-believers. I know too many Jewish atheists to count, and nearly all of them would say their religion is "Jewish" if you asked; I'm sure there are many people who grew up in other religious traditions who feel the same way. But here's the key political graph:
This is from exit polls, but there are other data that make the same point. For instance, in 2007, the unaffiliated made up 17 percent of Democrats, but in 2012 they're 24 percent of Democrats. The point isn't just that non-religious people lean heavily Democrat—we knew that already—but that they're becoming more Democratic. Why? My guess is that it's for the same reason that Latinos are becoming more Democratic, and African-Americans stay Democratic: Republicans.
If you don't believe in an all-powerful deity, you know that you're unlike most Democrats, just as you're unlike most Americans. But you also know that in the Democratic Party you'll find a lot of people who are like you and will welcome you. From the Republican Party, on the other hand, you get a message of unremitting hostility. Every time a bunch of dingbat Tea Party members of Congress gathers to say the Pledge of Allegiance and shout the "under God" part, every time Fox News ramps up the yearly installment of the War on Christmas, every time Repbulicans whine about how Christians are the real oppressed people if they can't get taxpayer money to prostelytize and force everyone else to listen to their sectarian prayers, non-religious folks get the message loud and clear: You're not one of us and we don't like you.
It's the same message Latinos get when they watch Republican presidential candidates accuse each other of not hating undocumented immigrants enough, and that African-Americans get when they watch the endless Republican efforts to make it harder for black people to vote. And the more you hear that message, the harder it becomes to even contemplate becoming a Republican.