Interesting, I grew up in eastern SD, pretty much right in the big cluster of deep blue counties in the middle of the country on the map.

I'm trying to think of what could be responsible for the above average outcomes in this area, and not coming up with much. The best reason I have is that it's a very family focused area. The 'default' path for most people is to get married, have kids, and put parenting before their career. This is quite different from what I see now, living in the bay area.