I'd go a step further and say that his winning the nomination is also in ASB territory. Not gonna happen. Not in any conceivable sequence of events. Not even if Mondale and Hart both drop dead in the middle of the campaign and John Glenn is caught with a dead girl or live boy. Jesse Jackson was not only supremely unqualified to be President and to have the nuclear launch codes, but America in 1984 was also still, and even among Democrats, not ready to elect a black President. His candidacy was tolerated in 1984 and 1988 because Democrats could not afford to alienate black voters.
Sorry if I sound harsh, but as someone who was around then, the idea is simply beyond the realm of even the remotely plausible. For all the racism we see today, things were even worse in 1984.