Iowa has much industry -- lots of farm equipment and meat processing. Dairying is much like factory work, so expect dairy workers to think much like blue-collar workers in the automotive industry. In contrast to states to its west it has little ranching activity. Demographics of Iowa are more like those of Minnesota or Wisconsin than like those of South Dakota, Nebraska, or Kansas.
To defeat President Obama in Iowa the Republican nominee will absolutely have to keep pounding him with incessant ads and frequent appearances that will cost the republican nominee dearly of opportunities better exploited elsewhere (like Ohio).
IA has tracked WI in particular very closely over the past couple of decades at least. It doesn't have a big racially-diverse city like Milwaukee, but it also doesn't have big conservative suburban counties like Waukesha either, so it's kind of a wash. It's really the suburbs that make WI (and to a lesser extent, MN), competitive for the Republicans; the rural areas in both states aren't as Republican as one might think from other nearby states.