Article about voting in the area where Trump held his rally today. It discusses why the area swung from Obama to Trump over the last couple of elections. It appears there was the "not voting for Hilary" which is why it went Trump's way but it does have some interesting explanations for it.
My church is one of the polling places in a solid Trump territory at the time. I was at church on election night for a meeting. People were bringing their kids in with them, I overheard them tell their kids this was an important election. One must vote for America (which I interpreted to be MAGA statement). The area around my church is a poverty area and one where there is a Hispanic population. We had a Hispanic ministry (now independent church) at the time. There was a belief that the Hispanic population were taking their jobs (although those complaining didn't want to work in areas like housekeeping jobs in the casinos or packing plant). So building a wall spoke to them.