From Iron Knee Political Irony:
There are many theories of why people support Donald Trump. One theory is that the voters are angry and hate the political establishment. Middle class workers have been hurt by the economy and are desperate to find someone who can shake things up. Or at least stand up to the special interests who are sucking our country dry for their own benefit. For example, an article in The New Yorker summed up Trump’s appeal this way:
The base of the [Republican] Party, the middle-aged white working class, has suffered at least as much as any demographic group because of globalization, low-wage immigrant labor, and free trade. Trump sensed the rage that flared from this pain and made it the fuel of his campaign.
But a detailed analysis of the 2016 American National Election Study has a simpler explanation.