Even with a record turnout of 66.7%, I think the answer is found in the third of Americans who didn't bother to vote.
Off hand one thing that Trump emphasized but didn't invent government sleaze. He one-upped Hillary on cronyism, filling the swamp with more gators and sowing government distrust among voters.
Politicians have spent decades telling voters their own government is screwing them. It appears at least a third of them believe nothing can be done about it.
There is the real silent minority....... SO disillusioned.....
The two party stranglehold............ If you are not voting for R or D=don't vote, that works for us, signed DNC & GOP