Disclaimers: 1) I didn't read the 14 pages of back and forth on this subject, so I'm not responding to any post, but instead to the original question. 2) I am not "for" Trump, and will probably not vote for him tomorrow as I don't think his temperament is suited to that required of POTUS.
That said:
First, a LOT of conservatives are willing to draw a parallel to Reagan with how Trump's wiliness in handling himself in the glare of the spotlight and against others is heads and shoulders beyond any other candidate in either party. The television media saw that and use it to pump up their ratings...just review the questions proposed by moderators in any of the debates...they throw out a hand grenade and the candidates obligingly jump on it for TV ratings. Let's call it: "Glam".
Second, a LOT of conservatives want corresponding actions by their candidates in office...to date with the current crop of candidates there is little and none to be seen. Trump does not care about a future career in politics, so he can say what he likes, and since he's free of the GOP machine, his followers see him as the best bet to push their agenda. Call it: "Independent".
Third, a LOT of conservatives see Trump as willing to say what no other candidate will; to wit: we see a multi-generational welfare system taking trillions with no appreciable gains nor end in sight. Call it "Frustrated".
Fourth, we see a broken immigration system that allows tens of millions of people to enter with no documentation, no identification, have various communities flout the national law with impunity (e.g. sanctuary cities), and take jobs (yes, that is a core belief) from citizens. And every solution (except complete capitulation) is terminally undermined by liberals and their politicians who defund, cat-call "Nazi", hide illegals, support illegals, etc. Call it "Disenchanted".
Fifth, we are ANGRY that people live for years on unemployment insurance instead of taking whatever work is available (see illegal immigration issue). Call it "Tired".
Sixth, We see our values (pillars of our civilization) being derided and sneered at by a liberal press and media. To wit: Religion is the basis for morality, yet is seen as antiquated; where heterosexuality and monogamy are second place to homosexuality and infidelity, where raising children is now the province of the government. A government that determines what they can say, what they can eat, and (coming soon!) what they can think. Call it: "Disgusted".
I could go on, but Trump hits these nerves like no other candidate and feeds off of them, so supporters of Trump see his Glam and Independence, and are Frustrated, Disenchanted, Tired, and Disgusted. I think that is a fairly good summary of why he garners so much support. Can Trump win a national election? IMHO, no, he can't get past a 40% "angry" base and the Dems will scoop up everyone else...unless there is a 3rd party candidate.
Please, this is just silly. 
