[O]ver the past few decades, the Republican Party has driven away people who live in cities, in highly educated regions and on the coasts. This expulsion has had many causes. But the big one is this: Republican political tacticians decided to mobilize their coalition with a form of social class warfare. Democrats kept nominating coastal pointy-heads like Michael Dukakis so Republicans attacked coastal pointy-heads.
What had been a disdain for liberal intellectuals slipped into a disdain for the educated class as a whole.
Republicans developed their own leadership style. If Democratic leaders prized deliberation and self-examination, then Republicans would govern from the gut.
Ultimately, this has meant that the more educated sections of society have been staying away from the Republican party:
The political effects of this trend have been obvious. Republicans have alienated the highly educated regions — Silicon Valley, northern Virginia, the suburbs outside of New York, Philadelphia, Chicago and Raleigh-Durham. The West Coast and the Northeast are mostly gone.