Another devastating ad from Veterans Against the Deal, this one even more emotional than the last. I’d like to believe these spots are helping to change the tide of opinion in the Senate, but the first one from this group, released Monday, explicitly targeted red-state Democrat Jon Tester at the end. Three days later:

After thoughtful deliberation, it’s clear @TheIranDeal is the only option right now to stop #Iran from developing a nuclear weapon.

— Senator Jon Tester (@SenatorTester) August 13, 2015

According to HuffPo’s updated whip count of Senate Democrats, 20 Dems are already publicly committed to supporting the deal and another 11 seem very likely to. Twelve more are “on the fence” and being lobbied heavily. Thanks to Bob Corker’s grand sellout, assuming all the “very likely” yeses end up voting that way, Obama would need just three of the 12 fencesitters to ensure that the GOP can’t stop the deal from being implemented. Among those 12 are Harry Reid, who has nothing to lose by voting yes, and Obama ally Chris Coons from deep-blue Delaware, so really all the White House needs is one of the remaining 10. Implementation is a fait accompli. In fact, if eight of those 10 sided with Obama, Democrats would have enough votes to filibuster the GOP’s resolution disapproving of the deal. I doubt they’d do it, for the simple reason that there’s enough political risk in Iran cheating on the deal that they’d prefer to have the lame-duck take formal responsibility for denying the GOP’s bid to defeat it. Presumably some Dems will vote yes on cloture and then vote against the Republican resolution in a losing effort so that the bill lands on Obama’s desk. The only mystery is what the final tally will be once Obama vetoes it and it returns to the Senate for an override attempt. Will enough Democrats be freed to vote with Republicans so that McConnell gets close to the 67 votes he needs, or will Dems hang together and deny McConnell even as many as 60?

Actually, maybe they’ll allow cloture to pass on the initial vote for the GOP’s resolution of disapproval, thus ensuring that Obama will have to veto the bill, and then filibuster McConnell’s subsequent attempt to override the veto. That way Obama takes most of the blame for the final outcome and Senate Dems earn some gratitude from their base by protecting him from the override attempt.