At the park and in the conference room, the air was charged with a state of urgency that did not yet approach panic but was not so distant from it. After Joe Biden’s incredible string of victories on Super Tuesday, just four days earlier, a new phase of the Democratic primary campaign — one that greatly disfavored Sanders’s once-unstoppable candidacy — was now underway. Former opponents and media pundits were coalescing around Biden, the newly restored front-runner, all but demanding closure to the horse race — essentially, for Sanders to pack up and go back to Vermont. Sanders had a different view of the situation: In so swiftly closing ranks, his detractors were inadvertently proving the case he had been making all along.

“Look,” he told me, “we are taking on the establishment. Wall Street is now opening up their checkbooks for Biden, because we are a threat to them. The pharmaceutical industry strongly supports Biden. Health care stocks went up after Super Tuesday. So, no, I’m not shocked by this.”

I suggested to Sanders that while his candidacy was demanding soul-searching on the part of the Democratic Party, it was his failure to persuade its most reliable constituents — African-American voters — that had led him to this precarious moment. But the candidate remained fixated on his adversaries. “Look, what we’re trying to do is take on the entire political establishment,” he repeated. “We’re taking on the entire corporate establishment, the entire media establishment. The real question,” he continued as he edged toward the doorway, “is: A year ago, would somebody have believed that a grass-roots coalition would be where we are today, a few points behind the establishment candidate? That is the real question. We’re taking on everybody! That’s something that has not been done in American history!”

The campaign was nonetheless scrambling to at least slow if not reverse Biden’s momentum. Sanders had in effect conceded the South to his opponent, canceling a long-planned rally in Mississippi while furiously concentrating his efforts on the Midwest. Several appearances were added in Michigan, which would host its delegate-rich primary in three days. A victory there might change the narrative once more. Instead, as we now know, Sanders’s defeat in Michigan seemed to many to be the moment his campaign ended.