New York City mayoral candidate Joe Lhota is making big noises about what morons his fellow Republicans are for shutting down the government. But he’s all in with one of their central demands—to delay Obamacare for a year.

The socially liberal, fiscally conservative Lhota, who has referred to “Tea Party crap,” said on WNYC radio yesterday, “The shutdown is a disgrace…. I cannot tell you how upsetting it is for me to see 30 extremists in Washington control the entire government.” He says “both” sides (natch) “need to come to the table and they need to negotiate.”

But Lhota shares the extremists’ negotiating point of putting off the Affordable Care Act for a year, because, he says, “there’s so much confusion about the individual mandate right now.”

Bill de Blasio, Lhota’s Democratic rival, said through a spokesman that Lhota’s “endorsement of delaying Obamacare puts him in lockstep with Republican extremists like Ted Cruz—extremists who would rather shut down the government and furlough thousands of New York City workers than see hundreds of thousands of New Yorkers get access to health care.”

But last night, Lhota, Cruz, the Tea Party, John Boehner et al. got a boost from some unexpected quarters: as rightwing blogs brayed, Jon Stewart slammed into Human and Health Services Secretary Kathleen Sebelius when she came on the show to push the ACA. After ragging (and rightly so) on the program’s technical glitches, an unusually obsessive and obtuse Stewart asked her five, six, maybe seven times why can’t the individual mandate to buy insurance be delayed for a year like the mandate for businesses has been?

Fair question. And it has an obvious answer (more on this in a minute, but in short, delay=death) that for some reason a nervous Sebelius could only dance around and Stewart acted like he’d never heard of.

When she gave tepid or partial answers—like, the employer mandate isn’t as big a deal as the individual mandate because most businesses already provide insurance—he seemed unable to follow, and asked, “Am I a stupid man?”

Of course not, Jon, but, as you’ve said of Fox’s Gretchen Carlson, you’re playing one on TV.

The answer to his question is simple, and Stewart is surely acquainted with it: without the individual mandate, the whole thing collapses. That mandate is the ACA’s cornerstone; the employer mandate is a bunch of bricks. Delaying the individual mandate by a year is tantamount to killing it. (Which is why, of course, the Tea Party considers delay the next best thing to repealing or defunding Obamacare.)

From Wonkblog’s Sarah Kliff: “The Congressional Budget Office estimates that, without an individual mandate, 11 million fewer people would gain coverage next year.” And those that do buy coverage would be the older and sicker people, which would cause premiums to spike and drive away the healthy even more.

“The individual mandate is a lynchpin policy, one that makes the rest of the Affordable Care Act work by bringing millions more people in the health-care system,” writes Kliff. “The employer mandate, by contrast, is more of an extra nudge, aimed at encouraging companies to keep doing something they already do right now.”

Sebelius had trouble saying this plainly, but just as some of her answers started to take shape, Stewart fell back on complaining that the ACA is a “market-based solution.” He wanted single-payer. Yeah, well, a lot of us do. But that train left the station years ago, and the train we’re riding now will wreck only if millions don’t sign up, especially millions of the young people that all too often laugh on cue at anything Stewart says.

Like in his monologue at the end of the show: “I still don’t understand why individuals have to sign up and businesses don’t, because if the businesses—if she’s saying, ‘Well, they get a delay because that doesn’t matter anyway because they already give healthcare,’ then you think to yourself, ‘Fuck it, then why do they have to sign up at all?’ But then I think to myself, ‘Well, maybe she’s just lying to me.’ ”

Clearly, someone needs to more forcefully explain this all to Jon. Someone, other than Bill Clinton, who could get on The Daily Show, someone who’s out there campaigning anyway. Someone like… Bill de Blasio?

Leslie Savan writes on how the media is playing fast and loose with ideological labels on both sides of the NYC mayoral race.