I’m not arguing anything you say, here. But both IOWA and the South are notably deeper benched with evangelical voters and religious right than are blue states, labor interests, and the socialists residing predominately in the North.
Polling has indicated that even the Evangelical vote is split pretty evenly between our two contenders. FR is only one example.
Elsewhere there are those who do support TRUMP, but who are on the QT about it. Some private poll reported that TRUMP may be polling 6-8% lower than he actually is, because of some of the voters who can’t say it out loud. I presumed it may be some Independents, but mostly moderate Democrats and maybe some Evangelicals. Who knows.
I believe you aren’t paying attention . Trump is leading in most of the south