Since this incredibly stupid term is rearing its ugly head again, some things need to be pointed out:
1-"Reagan Democrats" by and large were not blue collar union workers. For proof go look at the 1984 results in Western Pennsylvania or the West Virginia coalfield.
2-Most "Reagan Democrats" ceased to even be Democrats after that. They were mostly the white blue dog southerners.
3-Reagan was last in an election 32 years ago. The youngest people who voted for Reagan are going to be 50 years old. And these would be people who voted for him in his first election, not consistent Democratic voters prior to that.
Basically the actual Reagan Democrats are all either in retirement homes or dead today. They're not commuting to their stereotypical blue collar job listening to John Mellancamp and Bruce Springsteen along the way and there's no group of people or demographic today that could be accurately defined as even sharing the traits of "Reagan Democrats" who are an important swing demographic. The term is meaningless as applied to any 21st century election. You might as well talk about "LBJ Republicans". So no, Trump is not going to win any states on the strength of "Reagan Democrats", the few that remain might vote for him but they've been voting Republican for decades now already.
It's good posts like this, BRTD, that make your attention whore posts about scene bands, hipster Christianity, and suburbs all worth it.
