i pointed out previously that in order for the left to win the primary in the states, they have to sweep the midwest and find a way to split the south. if bernie is the guy, so be it.
that said, bernie may want to be seriously considering the idea of a black running mate as a compromise/consolation - and don't look too badly into that. i'm just inherently cynical. so, frame it as a way to reach out, then. if this is a serious tactic, you should get the candidate running early.
so, let's say that bernie talks nina turner into running, for example. the way this would work is that she'd run strong in the south, with the intent of taking votes away from kamala harris particularly - and even a 5% swing could be decisive. then, when he wins by sweeping the midwest and splitting the south, he offers her a spot on the ticket, which is a concession because she got x% of the vote.
it doesn't have to be nina turner, of course, although she's kind of ideal for the task.
i'm just trying to throw some tactical ideas out there that are dialectical in nature. bernie wants to run as a uniter, and that's fine, in fact it's great, but it means finding smart ways to split the field and unite it at the same time.
so, if you know you have to split the south to win, and you realize that the way you fix that in the end is to offer a space on the ticket, then you get your candidate out there early. that way, you can accomplish your task, while getting the candidate you want, in the end.