Over at the Washington Post’s Wonkblog, Max Ehrenfreund has a unique explanation for why Republican counties like Cobb and Gwinnett, which went for Mitt Romney in 2012, were won by Hillary Clinton in 2016.
Voters there had largely recovered from the Great Recession and its housing bubble burst. A paragraph:
Obama–Trump counties were no different from the other counties that Trump won, at least in terms of typical housing prices. Romney–Clinton counties were especially affluent, though, with a median home price above $300,000 — twice that of the typical county carried by Trump. These well-heeled places included traditionally conservative communities such as California’s Orange County, Utah’s Salt Lake County and Georgia’s Gwinnett County, which is outside Atlanta.