regional income distribution & resentment of government redistrbution

Poor areas are more likely to resent income redistribution since incomes in poor areas straddle the poverty line and recipients of government largess are very visible.

The 50% of the people above the line resent the 50% below the line who may receive government benefits.

In addition, because the young and educated move away from these areas, the remaining population tends to be older and sicker than the US as a whole. These folks typically receive social security/medicare/medicaid, which also raises the notion of people being on the dole.

And of course in Southern Appalachia, you can add in the element of crypto-racism.

The lower middle class in these areas are not being totally irrational; government support programs are very real and very visible.

Republicans of course are playing the class warfare game here, but in this case it's not rich vs poor; the class division cleaves between the almost poor vs the actual poor.

So Republicans wage class warfare at both the top of the income pyramid (such as the Koch brothers and all the way down to Todd Henderson, the law prof at the University of Chicago) as well as at the bottom.

It's an effective split, allowing Republicans get their funding from the top tier and their votes from those beginning just above the bottom tier.