Via Roll Call, if the House defunding bill can’t pass the Senate then obviously the money appropriated for ObamaCare will continue to flow. And a filibuster would, of course, prevent it from passing the Senate. Alternate headline: “Who’s the RINO now?”

He’s playing his strongest card here, namely, the fact that the filibuster would spare weak red-state Democrats like Pryor and Landrieu from having to take a tough vote on defunding ObamaCare. If Cruz and Lee convince Republicans to filibuster the House bill, then Pryor can vote for cloture while claiming, just like McConnell, that he’s voting to defund. That protects him back home with conservative voters while ensuring that there are no bad consequences to his vote for Democrats; the bill will have been filibustered, after all, so Pryor’s vote is meaningless. Without the filibuster, though, Pryor will have to vote on Reid’s amendment stripping the “defund” language from the House bill. That vote will split on party lines and Reid can only afford to lose three Democrats from his caucus to get to a simple majority of 51. That means one or more red-state Dems who are up for reelection next year — Pryor, Landrieu, Hagan, Begich, and so on — will have to bite the bullet and vote yes, then go home and explain why to angry conservatives. Who wants to volunteer?

McConnell’s message, in other words, is that a vote on Reid’s amendment is a do-over for Democrats on ObamaCare. If red-state Dems have concerns about the law, now’s their chance to vote with the GOP on defunding it. That talking point does, at least, have the virtue of turning up the heat on the other party instead of turning it up on one’s own. And yet, I’m still surprised that McConnell volunteered to be a pinata for grassroots conservatives by taking the lead on this instead of voting with Cruz in an ultimately futile filibuster bid. As I write this, the Senate Conservatives Fund PAC founded by Jim DeMint is leading with a post about him (and Cornyn) titled, “The Ultimate Betrayal.” He’s going to be the lightning rod for a backlash in the primary now. Why not let McCain or, better yet, someone with conservative cred like Tom Coburn make the case against filibustering?

Oh well. Reid boasted earlier today that there will be no filibuster, which is true. Now that McConnell and Cornyn have nixed it, the question isn’t whether Cruz and Lee can marshal 41 votes, the question is how few they’ll end up with. Rubio, who needs to rebuild his own cred, is with them, but Lindsey Graham apparently went so far as to say that he’ll vote for cloture in the name of avoiding a shutdown even after Reid strips out the defunding language from the House CR(!). Sure are a lot of emboldened RINOs out there right now. Maybe they’re calculating that the PR damage to the party in the wake of a shutdown would actually be more dangerous to them in the general election than a conservative insurgency would be to them in a primary. If so, that’s … a lot of PR damage.

Per Gabe Malor, looks like Boehner will have a single day — Sunday — to decide what to do about defunding before a shutdown occurs, assuming Reid’s schedule in the Senate proceeds as everyone expects. Exit question: Will the House move this week to pass something new before the Senate’s done killing their current bill?

Update: Betsy Woodruff of NRO posted this at around 2:10 ET:

https://twitter.com/woodruffbets/status/382567485289299968

They don’t have 41 to block the House CR but Cruz can seize the opportunity to launch a broadside against ObamaCare on the floor a la Rand Paul’s epic attack on drone policy this spring. Might want to turn on C-SPAN 2 right now if you’re near a TV (or click here). As for how long he’s planning to speak:

Cruz goes into Senate chamber. I ask how long he'll talk. His reply: "We shall see." Ignores other questions.

— Chad Pergram (@ChadPergram) September 24, 2013

Update: To clarify: This isn’t a true filibuster in the sense that it’s designed to stop the Senate from voting tomorrow on the House CR. As I understand it, because that vote is already set, it’ll happen regardless of how long Cruz talks.

Update: More from Woodruff:

https://twitter.com/woodruffbets/status/382572557406588928