Franklin Pearce / Boston Herald poll had a really interesting split they published. The poll ran Sept 30 thru Oct 4.
The polling done prior to Trump's diagnosis was running 46-41. The polling done after was 55-34 !!! The net poll result was 51-37.
I saw some comment about another poll that had a similar (but not as extreme) type of swing.
In no way do I expect Biden to win the popular vote by 20%, but it does make me wonder if this is the nail in the coffin. We know Trump is bleeding in the suburbs, particularly among women.
I can see plenty edge Republican leaners being put over the edge here. The debate just sort of reinforced what you already knew about Trump, so that might not have really added new information.
But these are the same voters putting their kids in masks every day to go to school, avoiding crowds, wearing masks in their day-to-day activities, and generally trying to do their part to be responsible. Trump is painting a pretty stark contrast.