Perhaps it could be that the majority of Americans are small 'c' conservative much the same as the majority here in Europe. Apathy is usually responsible for the periodic election of left wing governments. Here in the U.K. a centre-left Labour government under Tony Blair lost all credibility under Gordon Brown. In opposition under Ed Milliband it moved further left and lost a further election, now under Jeremy Corbyn it has become almost Trotskyist and is deemed virtually unelectable.  
Trump knew the genuine concerns of the American people and that left-wing idealism only appealed to the minority and had he not come across as somewhat bizarre he would have had a landslide against an opponent who seemed to be universally disliked and mistrusted.
David Cameron, a canny politician but never a true Tory, paid the price for betraying what his party had always stood for. Trump, it seems to me has his finger on the pulse of your nation and the 'sky definitely will not fall'.