I've always been amazed at just how liberal DuPage County is for a white upscale suburban county that isn't in the uber-liberal commuting direction (which in Chicagoland is the north shore). It tends to vote for liberal Republicans downballot (by "liberal" I mean tax cuts and social liberalism); people like Bruce Rauner do well there. But it's incredibly liberal given that it didn't even vote for Mitt Romney. In virtually every other midwestern metro, a county like DuPage would be solidly Atlas blue on the presidential level.
It's majority white, but not by as much as most other midwestern suburban counties. Also, Chicago being so much bigger, DuPage filled up a lot earlier than suburban counties in other states. You don't have any really exurban parts of DuPage; those are in other counties farther out (e.g., Kane).
