what I find interesting though is why eastern Tennessee hasn't swung dem. I know that sounds preposterous but here is my reasoning: East Tennessee is similar to Vermont in the sense that it is largely mountainous, overwhelmingly white, anti-slavery/pro-union, and opposed to the south. When the south started becoming republican by the 90s, Vermont swung to the dems. What separated an area like VT from East Tennessee, which has state republican?
No. Don't try drawing comparisons between ET and Vermont. ET is more like WV without the unions. They might have not wanted to secede, but the are still racist and were eventually able to reconcile their differences with the south.