My thesis is that the approximate 14% is timeless--rabid racists who would be guaranteed to support any equally rabid (or apparently rabid) racist running for the Presidency, whether George Wallace or Donald Trump or David Duke. They're inherently authoritarians, because they're pursuing the fever dream that installing a racist Supreme Leader in the White House will magically wipe away a half century of social progress that has rendered their racism contemptible. Trump's clarion call is his attack on the rightwing fantasy of "political correctness".

Your 40% comes from adding a notional 26% who have been converted by Fox "News" propaganda. This is where we get all definitional, because I would categorize those people as "persuadable", even if it took 25 years of relentless pounding to do it. Or maybe "malleable" is more accurate. And their motives are more debatable--economic issues are more likely to overshadow a nascent prejudice, though it's Trump's demagogic "genius" to frame the economic problems as racial ones, to unite those two threads of ignorance into a powerful electoral force.

How about we're both right? I define the floor of Trump's basement of support at 14%, you define ground level at 40%. And FYI, I think the popular vote for Trump in November will be much closer to 40% than 14%. It's after the election is over that the 26% will melt away, leaving that 14% revenant even more bitter and angry.