It’s not yet a Kamala Harris-style death spiral, but Elizabeth Warren doesn’t have much time left for correction, either. Three months ago, the Massachusetts Senator looked as though she was on the cusp of taking over the Democratic presidential nomination race. With just a month to go before the Iowa caucuses, Warren has dropped to fourth place in fundraising — and below her own high-water mark.

Politico’s Alex Thompson writes that this is a signal that activists might have tired of Warren’s schtick:

Sen. Elizabeth Warren’s presidential campaign announced Friday that it raised $21.2 million in the fourth quarter — significantly less than progressive rival Sen. Bernie Sanders’ $34.5 million haul over the same time period.

Warren’s fundraising total — less than the $24.6 million she raised in the previous quarter — is the latest sign that the grassroots energy behind her campaign has dimmed in recent months as she faced attacks from rivals and spent several weeks trying to explain her position on Medicare for All.

She also raised slightly less in the fourth quarter than other top rivals former South Bend Mayor Pete Buttigieg ($24.7 million) and former Vice President Joe Biden ($22.7 million), both of whom attended high dollar fundraisers which Warren forswore.

On its own, a $21 million quarter isn’t exactly bad news. A number of Democratic contenders would be thrilled with this kind of performance, especially without big-ticket donor functions. However, momentum matters in primary races, and with it the appearance of long-term viability. When a senator with a big media following can’t beat the mayor of South Bend, Indiana in raising funds — and trails the chronically mediocre Biden in the same metric — there’s a problem.

Did the small-donor focus make up for the damage to optics? Not really, because Warren comes up in second place on that score too:

Her average contribution was $23, compared to Buttigieg’s $34 and Biden’s $41, the campaigns reported. Biden also changed his position this fall to support an outside “Super PAC” largely funded by big donors.

The fundraising success of Sanders, whose average donation was $18, is the latest sign that he has been able to retain many left-wing supporters that the Warren campaign was hoping to peel away.

It’s not just a decline in fundraising, either. As we have noted before, this tracks with a more significant decline in polling that began at the start of Q4 and has only recently plateaued. At least Warren hasn’t dropped to fourth place:

The Q4 results basically confirm that this is not just a polling aberration. Voters are walking away from Warren, and they are taking their money with them. Activists might be leading this trend, FiveThirtyEight’s Seth Masket writes, and he thinks he knows where they went, too:

In my last round of interviews with Democratic activists in early-primary states, Sen. Elizabeth Warren, at long last, seemed to be getting traction. Forty-eight percent (14 of 29 activists I interviewed) said they were either supporting her or considering supporting her. However, the most recent results suggest that has changed. Activists still haven’t coalesced around any one candidate, but former Vice President Joe Biden has made gains in this survey. …

So as in previous rounds of this survey, I also asked those who were uncommitted to tell me who they were considering supporting.3 Warren still leads by this metric, as she did in October, with 13 of 31 activists (42 percent) supporting or considering her in this round, but Biden is in a close second place with 12 of 31 (39 percent) considering him. In October, only nine out of 29 activists (31 percent) were considering him. Booker, Klobuchar, Buttigieg and Sanders round out the upper tier of candidates being considered, with between seven and nine activists considering each of them.

This sounds more like activists coming to a practical decision to line up behind an inevitability. They might not like Biden’s attempts to play the middle against the extremes, but he’s pliable enough to at least suggest a potential opportunity to shape an incoming administration. Sanders won’t win a general election, and Warren’s unable to close the sale with Democratic voters. It’s either get on board the Biden Malarkey Bus now or get left behind.

If they get on board, though, they will want to shape the ticket. Warren’s got too much baggage for a running mate, and Bernie’s an even worse choice. Who will they want Biden to choose? Amy Klobuchar would be the safe choice, but look for someone much more sharply left-oriented.