Yesterday I wrote that the real suspense with Manchin’s alternative to H.R. 1 wasn’t whether he can get 10 Republicans to support it (he can’t) but whether he can get all 49 of his Democratic colleagues to do so. There are things in his compromise bill that won’t go down smoothly with progressives, most notably mandatory voter ID in all 50 states.

But he had an ace up his sleeve, it turns out. There’s no progressive in the country who’s more influential within the party on voting rights than Stacey Abrams. And I’m gonna guess that she and Manchin discussed his bill before he revealed the major points yesterday, with Manchin securing Abrams’s endorsement behind the scenes. He knew that having her onboard would give cover to leftists in the Senate who are wary of supporting his bill for fear of how the progressive base might react. Now that Abrams has given it her blessing, it’s safe for the Bernies and Warrens in the caucus to vote yes.

Which means the odds of Democrats getting to 50 just rose considerably.

The question now is why Abrams agreed to support a heavily diluted version of H.R. 1. Why didn’t she demand that Manchin drop his compromise, nuke the filibuster, and pass the bill she and the left really want? Bear that in mind as you watch, then read on.

BREAKING: "Absolutely."@staceyabrams says she could support @Sen_JoeManchin's voting rights compromise.pic.twitter.com/54X5mwZT9D

— John Berman (@JohnBerman) June 17, 2021

Even stranger, as Nate Cohn pointed out, Manchin’s bill looks quite a bit like the Georgia election law that Abrams has spent the last several months screaming about:

One fun anecdote on this note: the vaunted cost-of-voting-index, which initially ranked Georgia as the 49th toughest state to vote in, revised Georgia's ranking to 25th–the largest shift of any state in their 'revision'

— Nate Cohn (@Nate_Cohn) June 17, 2021

What’s she up to here?

Two things. Although voter ID got most of the headlines yesterday since it represents Manchin’s olive branch to the GOP, the most substantive provision in the bill is the proposed ban on partisan gerrymandering. Manchin wants to use computer models for redistricting instead. Abrams figures this bill is a bargain worth making if it ends up nuking the power of Republican-controlled legislatures in purple states — like, say, Georgia — to draw district lines in ways that guarantee that a disproportionate number of House seats are safely red. An end to partisan gerrymandering would redistribute Georgia’s black Democratic voters more neutrally, potentially threatening several Republican-held seats.

Senate Republicans aren’t going to go along with that. They’re not going to go along with any Democratic voting bill, I’m convinced, even one authored by a red-state centrist like Manchin because the base would view it as condoning “cheating.” Republican state legislatures spent this past spring writing “election integrity” laws in response to Trump-fueled suspicions of fraud last November. For Senate Republicans to support a Democratic bill overriding those laws would be deemed a major betrayal by GOP voters — even though the laws that have already passed in Georgia and Texas are far more modest in their reforms than Democratic scaremongers would have us believe.

So if Manchin’s bill is doomed because it can’t get 60 votes, and Abrams surely knows that, why is she backing it? What she really hopes to gain here, I think, is momentum in nuking the filibuster. Manchin is the main (but not only) bulwark against that in the Senate and seeing his own compromise bill torpedoed by Republicans might weaken his resolve. But Republicans can’t be blamed if Manchin’s bill fails to attract unanimous Democratic support. If Bernie Sanders and Raphael Warnock and whoever else balk then the filibuster isn’t Manchin’s big problem, the left side of his own caucus is. By endorsing the bill, Abrams is trying to herd those lefties into supporting it. If they do, and then the GOP tanks it on a party-line or mostly party-line vote, Manchin will face a reckoning on the filibuster. Is he prepared to see his own bill die or might he support a tactical nuclear strike in which he agrees to reduce the threshold for cloture from 60 votes to 55?

That might be worth it for Abrams and other progressives. If they can make Manchin bend on the filibuster, it makes the wider progressive agenda a bit more viable in Congress, especially if they have a good showing in 2022 and/or 2024.

The dilemma for the GOP is whether they should dare Manchin to go nuclear or agree to a watered-down version of his bill in the name of averting that. It’s possible, if unlikely, that Manchin would go fully nuclear and get rid of the filibuster altogether if they reject his voting compromise. If that happened, Dems could then pass his bill and get rid of partisan gerrymandering without needing any Republican support, which would be a terrible outcome for the GOP. As a Twitter pal said, centrist Republicans may calculate that it’s in their interest to counteroffer by agreeing to support Manchin’s bill *if* he drops the gerrymandering provisions (and most of the campaign-finance stuff). That would signal a willingness to compromise, making it harder for Manchin to justify going nuclear, and it would also put progressives like Abrams on the spot. Is she still willing to back his bill if the gerrymandering part of it gets dropped? If she isn’t then suddenly progressives rather than Republicans would be to blame for tanking the bill, which would be a good outcome for the GOP.

Abrams’s endorsement of the bill is the first move in a chess match, in other words. The next move is for Dems to make sure they really do have all 50 behind Manchin’s bill. Then it’s the GOP’s turn.