I know no one wants to spend a few hours on a Friday night watching another party’s presidential debate but you need to appreciate the opportunity tonight presents. Rarely will you get a chance to see a universally known politician go from de facto frontrunner to Hindenburg disaster in the span of five days. The flop sweat from Biden onstage tonight will be so profuse they’ll have to lay down a tarp beforehand.

Imagine how many phone calls Obama has gotten since Monday night from liberals begging him to endorse and prevent Biden’s collapse. It’s now or never, Barack.

But you know what? It might already be too late. New from Suffolk:

Bernie Sanders is holding steady at 24 percent, but Buttigieg is up four points over last night with 23 percent, a virtual tie in a survey with a margin of error of 4.4 percent.

Elizabeth Warren takes over third place with 13 percent, and Joe Biden slips to fourth with 11 percent…

Among women, Warren is down four points from Wednesday night and Buttigieg is up six.

And among voters over 65, a core source of Biden backers, Buttigieg has doubled his support overnight, a 16 point jump.

That’s a great irony of this race. The oldest candidate in the field is indisputably the favorite of the youngest cohort of voters whereas the youngest candidate in the field is surging past Biden to become the favorite of the oldest cohort. A second new poll, this one from Emerson, sees the same dynamic:

Bernie leads Buttigieg 44/17 among voters under 50. Buttigieg leads Bernie 31/20 among voters over 50. Biden is now third in that group, his alleged base, with 17 percent. And if you look again at that graph, you’ll see that his hold on fourth place is tenuous, with Klobuchar right behind him.

What happens if he slides to fifth on Tuesday night? He’s counting on South Carolina to revive him before Super Tuesday, but if we get another Bernie-Buttigieg one-two (or two-one) finish in New Hampshire *and* Nevada, I don’t know how many voters in SC will want to waste a ballot on Joe. His argument all along has been that he’s electable; by the time South Carolina votes, we might have three elections in the bag in which Biden finished fourth. What’s left of the electability case for Joe at that point?

And where does the money come from that’ll help him run competitive campaigns in Super Tuesday states?

The Atlantic has a premortem of Joe 2020 out today. Title: “How Biden Blew It.”

[F]orget about advertising and campaign staff: It’s now an open question whether Biden will have the cash to pay for his charter plane to fly him around the 14 Super Tuesday states that vote on March 3…

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.

Mike Bloomberg is shrewdly trying to choke off the available supply of big donors and other Democratic movers and shakers who might conceivably help revive Biden’s campaign, holding meetings with them and stressing that he wants their support but not their money. He doesn’t need it and won’t accept it, he tells them. All he wants is their endorsements, which will help mainstream his longshot bid and, more importantly, take those people off the chess board so that Biden can’t play them instead. If his plan works, he’ll watch Joe slowly starve from lack of donations before Super Tuesday. Increasingly it seems like even the expected victory in South Carolina won’t help him much in terms of either momentum or the money he’d need to run a long campaign afterwards.

In fact, a Biden victory from SC’s mostly black electorate has seemed so certain for so long that anything short of a dominating win will be treated by the media as another sign of weakness. A close second-place finish by Bernie Sanders in which he wins a surprisingly large minority of the black vote would make Bernie the winner for “narrative” purposes afterward. (“He’s not just ‘the white candidate’ anymore!”) Especially among a press that’s looking at Biden’s campaign right now and smelling blood.

I know I said this last night but it can’t be stressed enough: It is uh-may-zing how efficiently Buttigieg is eliminating Bernie’s rivals for him. There’s a fair chance right now that Warren is done after Nevada and Biden is done after South Carolina, mainly because Mayor Pete swooped in and somehow convinced anti-Bernie moderates that he’s a better bet than a twice-elected vice president *and* a twice-elected senator. Uh-may-zing.