I watched a video from MSNBC of all places that talks about the poll results in rust belt swing states. DT won these by <1%. Hilary had leads greater than Biden at this point. But she was still < 50%. It was just that DT was so low .There was a small but significant switch in the last couple of weeks. Those suburban women are what got him elected. Watching the polls this time around the numbers are not nearly as crazy, I think the pollsters are being much more careful or skillful. This should result in more accurate numbers. Remarkably though, Biden is over 50%, suggesting less room for swing voters
