Pay Quarterly Taxes, Become a Republican?

Interesting. Check out these charts showing trends in Republican voting, set against the national average:

Doctors and lawyers, plus clerks and other wearers of the white collar have fled screaming from the Republican party in the last several decades. Meanwhile, business owners, skilled workers, and unskilled workers have fled screaming to it. Business owners are obvious: Quarterly estimated taxes suck (I just wrote a check for my freelance income, and it hurts) and Republicans are the party of tax cuts. Has the changing economy given skilled and unskilled workers a more entrepreneurial sense of themselves and/or made them think more like business owners? Or is there something else going on?

Via Will Wilkinson