Then were are others who feel Trump is on their side, at least somewhat, and won't sell them out as so many other politicians have--making promises and not delivering for them and their class. I don't know why they think Trump will be different except that he's already rich, and therefore won't sell them out to become richer. He says he won't do that, but what makes it more believable from him than from countless others?
I don't totally understand the attraction Trump has for the second group, though I grasp it a bit. There is certainly reason to doubt that the GOP will follow through on their promises, especially promises to make the economy better for the little guy. The GOP has provided much more constituent service to business owners who want to keep wages and benefits low. They've done it by opposing more regulation, mandatory health insurance, and by not working toward enforcement of immigration law. The GOP helps businesses on labor issues (with de facto support of immigrant labor) by reneging on implicit promises to and screwing over the little guy wage earner. And the GOP has chosen the business guy again and again.
So I get Trump's popularity. I'm not sure what Trump means for the future of the Republican party. It's not surprising if the GOP business elite is finally losing control. They've let blowhard talk radio jocks be the spokesmen and missionaries, and maybe they're finally going to pay the price for that.
Or possibly they'll just pay a short-term price until things go back to normal:
...it would be better to effectively rent the party to Mr. Trump for four months this fall, through the general election, than risk turning it over to Mr. Cruz for at least four years, as either the president or the next-in-line leader for the 2020 nomination.What an excellent insight, though it may not be true. Maybe that's a third way Trump is attractive. In a no-win situation, he'll do less harm than the other potential nominees. He'll let those in the mines blow off some steam, and then will fade away as quickly as Mondale did.
Perhaps there's even another way he is attractive, captured by this quote: "I can’t stand Trump, but I love what he’s doing." And what is he doing that is exciting or admirable? Maybe it's calling out all the political hypocrites (except himself, of course). There are lots to be called out, and it's good that someone is doing it. However, that attraction isn't going to last because the seams in his own ideas will begin to fray with all his vigorous denunciations of all the rest of those hypocrites. How will it happen and how soon? Damned if I know. But it'll be exciting to watch.
Extras. Great reads about Trump: Is Trump disproving the theory that the party decides? If so, how and why is it happening? (From Nate Silver.) The GOP has no intelligence on Trump because they are completely cut off from his supporters. That's a risky position to be in. A sampling of readers of Dreher, many of who are religious, and why even they like the philandering, foul-mouthed gambling czar.