He had to walk a line today in communicating his determination to stay in the race. On the one hand, he needed to press the case that he’d be a better nominee than Biden would. On the other hand, barring a freaky-even-by-2020-standards development, nothing’s going to stop Biden from winning the nomination at this point. If you’re Bernie, how do you negotiate that? You need to hit Joe to give yourself even a faint chance of a comeback — but if you hit him hard and lose anyway then Biden has to face Trump in the general as a wounded man.

And the more bitter it gets between Biden and Sanders, the less likely Bernie fans will be to turn out for Joe in November.

Watch five minutes from this afternoon’s speech and you’ll find him keenly aware of that dilemma. Then read on.

At no point does he attack Biden personally. He refers to the upcoming debate on Sunday as one with his “friend.” He frankly lists all the issues he plans to raise there — Medicare for All, climate change, illegal immigration, and so on, almost as if he’s giving Biden the questions to a test in advance. That is, I don’t think Bernie’s hanging around at this point in the hope that he can win. (Although hanging around at least gives him a loooooong longshot chance of benefiting if Biden makes some sort of nuclear gaffe.) I think he’s hanging around to pressure the presumptive nominee into not straying too far from the progressive agenda as he gets ready to pivot to the center for the general election. It’s not about me, Sanders is saying, it’s about ensuring Biden’s commitment to left-wing policies. He’s going to support Joe this fall. But he wants to see a little support in return first.

That’s the most palatable way he can justify staying in the race. It’s not personal with Biden, it’s not a vanity candidacy, it’s to advance certain ideas.

But it’s also surely true that Team Bernie is hoping for a massive screw-up by Joe on Sunday night. Sanders and his acolytes have been claiming in ways more and less obvious recently that Biden’s too old and, uh, fragile for the job anymore. That’s what the dispute about standing versus sitting during the next debate was about; the last-ditch argument for nominating Bernie instead of Joe is that the 78-year-old with a still undisclosed heart condition is actually the healthiest person left in the race. The Sanders camp wants to give Biden at least one more opportunity to provide evidence that he’s senile before throwing in the towel. Making him stand there and talk in front of a national audience for an hour is a way to do that.

And what happens if Biden does sound shaky at points — and Democratic voters nominate him anyway? Well, lucky for Trump, I guess.

This speech was also a canny way for Bernie to pressure Biden into attending the debate in the first place. I’m sure on some Team Joe are considering this:

There is absolutely no benefit to Joe Biden or the Democratic Party to holding the Sunday debate. The race is over. Bernie's sole goal will be to try to damage the inevitable nominee. Bernie has lost and is angry about that loss, why give him free swings at the nominee?

— David French (@DavidAFrench) March 11, 2020

Maybe Biden could have bailed out before Bernie gave this speech. But now that Sanders has framed the debate as a sort of pop quiz on how much Joe values the progressive agenda, skipping it would feel like he’s snubbing not just Bernie but the entire Bernie base. That’s exactly what Democrats are worried about if the primary continues to drag out — new opportunities for hurt feelings between the nominee and a cohort whom he needs this fall. If Biden skips the debate, Bernie fans will call him a coward and accuse him of trying to run out the clock. If he attends the debate and pushes back on parts of Bernie’s program, they’ll be furious at his squishiness. If he attends the debate and sweet-talks Bernie’s program, he risks spooking the suburban voters who voted for him because they prefer something more moderate than democratic socialism. It’s hard to see how participating in this debate helps Biden in any way electorally.

But he has no choice now, realistically.

The most notable part of the speech is Sanders claiming, “While our campaign has won the ideological debate, we are losing the debate over electability.” That’s true in some ways. Even in a Biden landslide state like Mississippi, 62 percent of voters said they support a single government insurance plan for all. Bernie’s ideas have made inroads. It’s just that … none of the actual candidates who’ve embraced M4A have been very competitive. Not Kamala Harris. Not Elizabeth Warren. Really, not even Bernie himself:

A telling observation, from @saletan that illustrates how indulgent it is for Sanders to stay in this race: "[I]n 25 primaries and caucuses so far, he has managed to crack 37 percent of the vote in only three, even as the field has narrowed." This isn't 2016. It's not close. https://t.co/1B33eYQRPE

— David French (@DavidAFrench) March 11, 2020

It’s also true, as Sanders says in the clip, that younger Democrats are overwhelmingly pro-Bernie. Democratic socialism does appear to be the wave of the future in the Democratic Party. It’s just not the wave of the present — thanks in part to those same young Democrats, who aren’t turning out at nearly the rates Sanders needs:

#MOPrimary* Early Exit Polls:

18-29: 12% (-4 from 2016)
30-44: 17% (-8)
45-64: 35% (-2)
65+: 36% (+14)

Per MSBNC, Via @Brand_Allen

— Political Polls (@PpollingNumbers) March 10, 2020

That trend of underwhelming youth numbers has shown up in state after state. It’s Biden who’s the “turnout candidate,” as you can see from the burst among seniors in Missouri.

I think if Biden is conciliatory to him on Sunday — and he will be, given his comments about Bernie Nation last night — then another Joementum rout next Tuesday will convince Sanders to pack it in. If things get bitter on Sunday, hoo boy.