I think that from a political science point of view, the most electable candidates are those who win office in areas that are usually largely for the other party.
Andy Beshear, for example, is the governor of Kentucky. He's a Democrat, but he won office in Kentucky. I think he would walk into the White House if he won the nomination simply because he isn't Biden or Trump.
But, neither side will do this. It will be Trump v Biden, and I think Trump wins this time.
I also think that this is a major collective fail. The fringe has taken over. Most of us are more sane than fringe, but we can't (or won't) band together to stop it. We'll both still vote for "Our" fringe guy.