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Please, let me amend a bit my last response. It's not just racism, but also anti-intellectualism, an ethos of conformity, and suspicion of "the other" that this demographic mistrusts.
I'm speaking only from personal experience here, so please don't take this as any kind of scientific study, but in my experience, Hillary would appeal to this demographic because (in the simplest of terms) she doesn't come off as sophisticated or as someone who will rock the boat. She's a problem solver rather than a dreamer.
In my experience, dreamers are abused as faggots. Clinton's appeal is far more earthy, pragmatic, and lacking ambition.
I think this is probably more of a factor than race, frankly.