Running short on money is a big part of why he ended up here at all.

After a disastrous summer of fundraising, plans from the team in Iowa and other states would linger with national headquarters for weeks, then come back without approval for the spending being requested. Other candidates were quickly hiring staff—particularly Buttigieg, who in June had all of four staffers in the state but went into the caucuses with 170—while Biden’s team was under an almost complete hiring freeze. The campaign yanked its TV ads, leaving Biden dark for weeks and exponentially outspent in online advertising by Warren and Buttigieg, who soon had the rising poll numbers to show for it. At one point, aides realized, Biden was on track to spend less on TV in Iowa in this race than in his 2008 run, when he finished as an asterisk, with 1 percent of the vote.

Biden aides who were being honest with themselves knew for months that they were in trouble. Some didn’t want to believe it; some couldn’t. Others felt like they’d gotten into a taxi with a driver who was swerving all over the road, and they were just holding on and hoping they made it to the end.

They hoped that Democrats’ obsession with beating Donald Trump and voters’ sense of personal connection to Biden would pull them over the edge. Trump had blundered into his own impeachment out of fear that Biden was strong. Now they were hoping the impeachment trial would help make up for his weakness. “We might win this,” one person who worked on the campaign told me the week before the caucuses, “and it might come down to nothing we’ve done.”

When Biden held his final pre-caucus rally at a middle school in Des Moines on Sunday afternoon, 1,100 people came—his biggest crowd in Iowa of the whole campaign. Eight people introduced him; four retired senators were in the crowd. But by the time he began speaking, the Super Bowl had started, and people were dribbling out of the room. An hour earlier, a few miles away in a high-school gym, Buttigieg had drawn twice as many people.

[ Peter Beinart: Impeachment hurt somebody. It wasn’t Trump. ]

Biden himself has never been fine with how his campaign has been going, and he’s never been the serene-to-the-point-of-oblivious presence that his aides have made him out to be. Increasingly concerned about the day-to-day management of the campaign by junior aides, he turned to his older inner circle. They settled into a war-weary resilience. “There’s no joy in the campaign,” one Iowa Democrat who’s been watching the race closely told me ahead of the vote. People working for the campaign made the same point to me, though usually with more curses.

Biden’s late start, and his need to host high-dollar fundraisers in Los Angeles, New York, and Washington, D.C., limited the amount of time he spent on the ground in Iowa. So he rarely made the kind of traditional stops, like going table-to-table in restaurants, where his last-of-his-era, retail-politics virtuosity shines.