I am in the midst of reading,
The Great Revolt by Salena Zito & Brad Todd. It is an interesting book in that the authors traveled the back roads of the country to try and understand why the folks in 'flyover' country voted and continue to support Trump.
It all boils down to these quotes...
Trump supporters think: "I think a lot of the voters who vote for Trump
take Trump seriously, but not literally
."
Anti Trumpers think: "They are always taking Trump literally but
never takes him seriously."
The authors also speculate that Trump is picking up supporters albeit quiet supporters, every time the MSM goes into a frenzy. He is perceived as the underdog -David Vs. Goliath parable.
His supporters are also supportive because he is actually doing things he promised during his campaign. A rather unusual action for someone who runs and then is elected to public office.
Last, the only way for Trump to loose his supporters is to become part of the 'swamp'. I suggest a weaker person would - Going with the flow rather than going against the current.