Right now Biden is at 32%, Bernie is at 18% and the next tier are in the mid to high single digits. I think if either one gets pulled into the same numbers as the rest of the top tier, they’ll sink. If Uncle Joe has 4 times the polling as Kamala Harris, Elizabeth Warren, Mayor Pete or Beto it seems like a done deal and while Joe’s not perfect, he would be a good president.
If all those people are within a few points of each other, people are going to want to listen to all the alternative and Joe won’t be so compelling. His saving grace might be having South Carolina as a backstop. He’s wildly popular with Black Democrats in SC.