Imagine a demographic that has doubled its share of the population over the past two decades, is up by 25 percent over the past four years, and now accounts for as many as one in five Americans. Imagine that this demographic votes disproportionately for one political party—to the tune of 70 percentfor Obama versus 26 percent for Romney in the 2012 election. Sounds like a demographic that ought to be of interest to politicians, journalists, and activists, right?

That demographic consists of people who describe themselves as atheist, agnostic, or religiously unaffiliated—the “nones,” as they’re sometimes called. And it hasn’t attracted anywhere near the attention it deserves in the postgame analysis of the 2012 election.

A quick Google search turns up 64,000 results concerning the GOP’s “Latino problem” that became evident in exit poll data on Election Day. Latinos represented around 10 percent of the electorate in 2011, up from nine percent in 2008, and they voted for Obama at a rate of 71 percent. But it’s the nones that should be keeping Karl Rove up at night. Pew put them at 12 percent of the electorate in its exit poll data, and at 19.6 percent in its earlier general survey. (The difference appears to have more to do with polling methodology than with voting habits.)

The Public Religion Research Institute, in a studypublished on November 15, pegs the religiously unaffiliated at 16 percent of the electorate—and they figure that 78 percent of the category went for Obama. Crucially, like Latinos, the nones are young. One in three Americans under 30 are religiously unaffiliated—four times the rate for the over-65 cohort that keeps Rove in business. This isn’t a trickle, it’s a tsunami.