The continuing Democratic collapse among ancestrally Democratic voters seems to be one of the overlooked stories of the election thus far and is key to understanding what's been happening with non-college educated whites

Ancestrally Democratic areas across the nation--Southeastern Oklahoma, Southeastern Missouri, Middle Tennessee, the Ohio Valley--saw major shifts against the Democratic presidential candidate relative to 2016.

Trousdale County, TN--87% white, voted Democratic in almost every election from 1912-2008--was 67-30 for Trump in 2016. This year? Trump carried it 74-25.

Pike County, OH--97% white, Carter carried in 1980--was Trump 66-30 in 2016. Trump won it 77-22 this year.

But we can find a lot of very demographically similar places across the country that swung to Biden from 2016--Eastern Tennessee, for example. What explains this divergence?

Eastern TN has elected a Republican to Congress continually from 1870. It's an ancestrally Republican area, yet demographically similar to the rest of Appalachia.

I think what we can conclude is that in a lot of areas of the country, the ancestral identification with the Democratic Party still counted for something in 2016. What seemed like historical lows for Clinton look comparatively better now.

What looks like a divergence--some rural white areas swinging towards Biden and others swinging towards Trump--is actually more of a convergence of political opinion among rural whites.

And so the electoral coalition that sustained Democrats for the better part of a century is gone, probably for good. It was these voters that enabled the Democratic Party to hold the House of Representatives continually for over 40 years. No longer.