The case for a Biden comeback always presumed that voters would mostly cast their ballots based on their views about Donald J. Trump. That’s how President Biden won four years ago, and it’s why many believed he could overcome poor approval ratings to win again.

But as my colleague Reid Epstein noted Monday, this election hasn’t been about Mr. Trump since the recent presidential debate. Instead, the political conversation has focused almost entirely on Mr. Biden’s fitness for the presidency and whether he’ll remain his party’s nominee. So long as that’s true, the path to a Biden comeback will be long and arduous.

The best that can be said for Mr. Biden is that the worst of the post-debate crisis might — might — be over. My colleagues on the Hill report that House and Senate Democrats did not reach consensus that might have encouraged party leaders to try to nudge Mr. Biden out of the election. Even skeptics like Jerry Nadler, who had reportedly told his colleagues that Mr. Biden should end his candidacy, appeared newly resigned to Mr. Biden’s renomination. And all of this follows a steady stream of Democrats who affirmed their support for Mr. Biden on Monday, including Alexandria Ocasio-Cortez.

Months from now, it’s possible we’ll look back on the last 48 hours as a turning point for Mr. Biden — the moment when efforts to remove him were finally pushed aside, and when he and the Democrats got back to the task of trying to defeat Mr. Trump.

But while the worst might be in the rearview mirror, this challenging period for Mr. Biden seems far from over.

For one, his position remains precarious. If he has indeed made it through the worst, he did not do so mainly by assuaging doubts about his fitness for office. Instead, he endured because dissenting Democrats were unwilling to take the risky step of directly confronting him and his vocal allies.