I think the DNC has no choice except Kamala. The black vote is trending Trump but only about 25%. It could go much larger if they push Kamala aside. Joe is gone. The wise choice for the Dems is now to keep Congress from going Republican but I do not know how they will do that. Oddly Harold Ford would be a good choice for president by the Dems. He is eloquent, very smart and seems a reasonable man and is genetically white and black. In reality he is far left wing. I oddly fear him as a candidate.
Not a problem if they ditch Joe and Kamala and bring in Big Mike.
They have to go with Harris to keep the campaign cash I think.