Red States, Blue States, and IQ?
I smell an odor of bullsh!t arising from this. In the table cited, there's over a 90% correlation between mean income and mean IQ. I suspect it's something made up out of income statistics with a little scatter added.
As for why states with high incomes went Democratic … It may be that the middle-class majority in rich states are prejudiced against their wealthier neighbors and the middle-class majority in poor states are prejudiced against their poorer neighbors.