Very interesting paper. Two problems that jumped out at me are: 1) income is not COL-adjusted, and 2) more importantly, there is not a term in the regression fo

Very interesting paper. Two problems that jumped out at me are: 1) income is not COL-adjusted, and 2) more importantly, there is not a term in the regression for urbanization/population density. It is well-known that urban areas lean Democratic, and richer states are more urban. Thus the phenomenon may be reflecting urbanization rather than state wealth.