Education is tricky, because it’s tied up with so many other things. College graduates are generally more liberal; they’re also more insulated against unemployment and outsourcing than your average blue-collar factory worker (though that certainly could change). And, of course, there’s the ever-widening income gap between college graduates and everyone else. What looks like a strong correlation between higher education and opposition to Trump might just be a proxy for a hidden economic variable.

But if that’s the case, it’s not a simple connection. The education gap persists even when controlling for a county’s median income, its industrial base, and whether it has lost local manufacturing jobs. All those factors predict support for Trump, but not to the degree that education does. Neither does population density, a decent indictor for whether voters live in a rural or urban area.

Counties with well-educated residents consistently broke against Trump even when they weren’t particularly wealthy, as Nate Silver recently noted was the case with his hometown in Michigan. They voted Democratic even when surrounded by relatively red-leaning neighbors (see Harrisonburg, Virginia, or Asheville, North Carolina). Some of the counties hosted college towns, distorting their overall demographics, but not all of them. Something about living in a better-educated area made people favor Clinton, and it didn’t have as much to do with money as widely suggested.

The exception to that might be the rate of male unemployment, which rivals a college degree for predictive power. That’s not surprising: white working-class men have long polled as the base of Trump’s support, and the past two decades haven’t been kind to them. But while the connection seemed strong, our analysis indicated it was also more likely than the other factors to be a product of random chance.

So what is it? Trump voters aren’t stupid. I have a hard time believing that simply obtaining a college degree would convince a voter to view Trump as a charlatan and not a champion. I’ve previously theorized that a “hope gap” might explain Donald Trump’s appeal, with people in communities where most residents have fewer educational credentials having a dimmer view of the future. But it’s also possible that a region’s education level is simply the primary ingredient in a larger medley of cosmopolitanism, an indication of its integration with a global world.

The Republican nominee did worse in communities with strong minority populations (including a disappointing turnout among Asian voters, who are typically sympathetic to the GOP). Conversely, his support shot up in counties where very few residents have left their home state. Polling before the election suggested Trump voters were more likely to have remained in the communities where they were born; his electoral returns largely held that up. He also fared better in regions that have seen a recent influx of Hispanics, where there were few before.