If Biden wins almost certainly Harris, If Trump wins the field will be wide open I expect someone from the left wing to have a good chance at winning Id say Warren or AOC would be the most likely possibly Yang if Automation becomes a bigger issue
Warren will be too old and AOC won't get the nomination because she won't get the support of black voters. Same for Yang. In the event of a Trump victory this year, the 2024 nominee would almost certainly be Harris, but I could maaaaaaaaaaybe see Buttigieg or Klobuchar having a shot. Or maybe even Tim Kaine, if he decided to run.