At this point of time, he shall show his poise by appealing to unity of demorates and a best result for dem's nomination campaign, since Dem can't afford to such an endless self-destruction process. He can announce to democrates he is willing to accept any outcomes of the nomination campaign as long as it would give DEm the best chance to win upcoming general election.
He is too bold or naive to even think about this kind of strategy ... his campaign advisors such as that resigned Harvard professor is no brain either. They're just a bunch of inexperience, naive librals that pursue the campaign by just riding people "high" ......