Trump is accelerating a trend that was already happening: non-college educated whites moving toward the Republicans while college educated whites moving toward the Democrats.
Romney won college graduates by 4% last election.
Romney was the dead cat bounce, though. The long term trend has been there since at least 1992.
Bush 2004 won college graduates by 16%, Bush 2000 won them by 11%, Dole lost them by just 2%, and Bush 1992 lost by them by just 3%.
Where is the long-term trend that has been there since at least 1992?
There is no trend. There are differing levels of support depending on the GOP candidate. Highly educated conservatives tend to favor neoconservative, globalist, interventionist, nation-building positions. George W was a poster boy for this. Donald Trump is their worst nightmare.
Exit Donald Trump, re-enter the educated Right, given the right candidate.
