He appeals to racists, insecure men, big corporations and people who say openly that education is harmful. He ran against a woman, which secured him the misogyny vote.
He's a troll so general assholes will support him because it's fun. Fox news even said so out loud early in his campaign.
Some people have been indoctrinated to fear and hate democratic views.
Democrats are not perfect and Hillary was not their best candidate.
Also, he has all the qualities of a prosperity gospel preacher, luring a big chunk of the religious community and otherwise gullible idiots.
Stupid people want politics to be about showmanship rather than actual competence for the office, and few of us can say Trump is not entertaining one way or another.

A lot of small stupid streams make for a river once you put it together.

Maybe it’s because here in America we have are greatly divided and one portion in particular is so self absorbed that it fails to even recognize the others.
Or the other segment that feels as though they’re the greater of all segments of our society because they’ve convinced themselves that they are.

We also have another segment that’s being used as a scapegoat for the woes of another segment.
Nonetheless if you are not living in the areas where his support is the strongest or not working in the industries that have been affected by trade decisions made by a president nearly 50 years ago then no won’t get it.

Our country is divided and the division perpetuated on a daily basis we are conditioned to choose just ONE and reject all others. We’ve been made to encapsulate ourselves to only see what either pleasures or outrages us. And don’t worry the other side is suffering from the same condition.

But then you have those of us who see the problems and have tried to achieve solutions but the media will throw a new pleasure or outrage out there and once again the focus is lost.

And as far as trump goes he was per one of HRC’s emails to become a pied piper candidate and to clear a path through the republicans and if you’d read the emails would’ve seen that she handpicked her opponents when there was 8 more that most people never got here about.
And then Bernie was a backfire and when she wasn’t trying to sound like him the media was experiencing blackouts as soon as he said her name.

Add the fact that her campaign slogan and message had nothing about it that said she was doing this for us but instead the media clearly stated that we needed get in line behind her. Then she insults an entire segment of society that not only is the most consistent group of voters but in the last week her and her team told the world that they had this.

So it’s not as much of a question of how could someone support him but aren’t we trying to get a better set of candidates that will hopefully support us?

He "spoke" to their frustrations and dreams and they believed it.

As many times as I’ve thought about this same question, the answer still evades me. It’s completely beyond understanding.