Farm Crisis issue with Soybean Farmers maybe souring a bit might be a factor here?
"Free Trade" vs "Economic Protectionism" is not as cut and dry as many might think in IA.
Could be a blip on the radar, or a return to the collective memory of many older folks, and their kids that now run the Hog and Soybeam 80-160 acre family farm which is machine intensive rather than labor intensive and the insensitive response of Bush Sr and Dan Quayle to the farming crisis of '87/'88 that swung major parts of the "Grain Belt" DEM for the first time in Decades. (Factory Towns are their own bag in IA, although I believe Tractor Plants used to be a thing around these parts).
We'll need to see more out of IA, which I'm sure we will as the first State to present final results in the Caucus/Primary Season, but the image of Trump is more likely to be fixed than most of the DEM prospective nominees.
I hope so. I personally think that farmers will still end up voting for Trump anyway. Though I do feel confident in Iowa voting less Republican than it did in 2016. I think it even votes to the left of Ohio this time.
