Professor, we seem to be talking past each other. You emphasize the agency of Gov. Cuomo, I emphasize the utter impossibility of Democrats down-ballot running with someone who apparently is in early stage of dementia.Imagine debating your General Election opponent for Senate, House, or Dogcatcher - and being challenged to support the election of someone your party nominated for CEO of the US Government - someone who looked confused throughout a presidential debate with President Trump!
I dont want to exaggerate, but IMHO Biden is fully capable at this point of making utterly unacceptable statements on the biggest political stage. The Democrat Party can ill afford to be represented by someone in his (apparent) condition. My mother (formerly a schoolteacher, and considered the smartest of her seven siblings) was almost as smart as Biden seems now when I took her under my wing for her 5 year Alzheimers decline.
I have a hard time believing that any party would actually take that risk. One way or another, IMHO, the the Democrats will find a way to nominate a dark horse. And, pace your comment about politics downstream from culture, that dark horse will need gravitas. And that maps to being a present or recently retired governor of a high-profile state.
First, in this China Virus quasi-national-quarantine situation, ALL “down ballot” positions favor incumbents. And the longer it goes, the more incumbents will be safe. In most of these cases (House, lots of the state seats in blue states) , the DemoKKKrats would be the beneficiaries, even in a Trump landslide.
So I don’t think they are that concerned yet about the down-ballot issue. They were with Dinobernie before the CV, but now, I don’t think that’s such a concern. They know Trump will crush whoever they put up. If they EVER want to run Cuomo or someone else in the future, they don’t dare run him/her now and get blown out.
And nobody destroyed down-ballot like Zero, yet they stuck with him through two terms.