AP Photo Obama secures 41 votes in support of Iran deal Three key Democrats said they would back the agreement this morning.

President Barack Obama won decisively on the Iran nuclear deal on Tuesday. But the Senate’s war over the agreement is just beginning.

While the accord will survive Republican attempts to derail it, the Senate still faces a bitter fight over how exactly Democrats will stymie the GOP.


Right now, it’s not clear if Democrats will block a Republican disapproval resolution with a filibuster on the floor, or if President Barack Obama will have to veto the measure, a move that almost surely would have to be upheld by another vote in Congress.

Democrats argue that a presidential veto, and the weeks of additional debate the override process would eat up, could hurt the United States’ international standing. But Republicans are eager to put political pressure on Democrats and keep the focus on an agreement the GOP argues is a threat to Israel’s existence and weakens U.S. security.

Despite those concerns, and a fierce, multi-million dollar lobbying campaign against the deal from the American Israel Public Affairs Committee and others, Obama hit the magic number of 41 senators on Tuesday, denying Republicans a filibuster-proof majority in the Senate.

But rather than take a victory lap, Democratic leaders that support the deal are still working their members in preparation for a decisive Wednesday party lunch that will determine whether the Senate minority is prepared to mount a historic filibuster of the resolution.

“They don’t like the notion ‘filibuster.’ They had a bellyful of filibusters when Republicans were in the minority,” said Senate Minority Whip Dick Durbin (D-Ill.) of the colleagues he is canvassing. “Now we’re getting into the type of vote it is … nobody knows the answer to the question.”

Indeed, pro-deal Democratic sources hope the 41 members who support the underlying deal will stick together behind a filibuster, but there are no guarantees. And Republicans in both chambers are discussing the possibility of voting on Friday, Sept. 11, to put maximum political pressure on Democrats, according to senior GOP sources.

In a brief interview, Sen. Mark Warner (D-Va.) was noncommittal on the filibuster question and said he will "wait and see" to hear what the full caucus says during their first post-recess meeting on Wednesday. Sen. Richard Blumenthal (D-Conn.) said it could be confusing to vote one way on a procedural vote and another way on the final disapproval question.

“I may still vote against cloture because I’ve taken a position on the merits and that I’m just afraid it sends a different message if I vote a different way on cloture,” Blumenthal said in a telephone interview Tuesday.

What Democrats really want is to set up a vote that blocks out the parliamentary noise and boils the Iran debate down to a single, easily understood roll call vote. Even those Democrats that oppose the Iran agreement say they support one vote on a disapproval resolution set at a 60 vote threshold, the typical bar for most Senate business.

“I’m for an up or down vote,” said Senate Foreign Relations ranking member Ben Cardin (D-Md.), one of four Democrats to oppose the deal. “It should be a 60-vote threshold. That’s what we all thought it was going to be.”

But Democrats aren’t going to get what they want. If they want to block the Iran resolution, it will be on the GOP’s terms.

After repeatedly noting Senate Majority Leader Mitch McConnell’s history of leading filibusters for eight years in the minority, Sen. Harr Reid (D-Nev.), the Democratic leaders, asked on Tuesday afternoon for an agreement to vote on the resolution at a 60-vote threshold later this week.

McConnell (R-Ky.) flatly rejected the offer, instead proposing an “up-or-down” vote with a 50-vote threshold, while portraying a potential Democratic filibuster as obstruction and “obfuscation to shield the president” if Democrats use the chamber’s supermajority requirement to reject the resolution.

The two leaders battled to a stalemate on Tuesday, making it likely McConnell will set up a vote to break a filibuster for later this week. If McConnell moves to do so on Wednesday, the Senate would vote on Friday Sept. 11 on whether the resolution should be taken up by the Senate for a simple majority passage vote. At that point, it would pass the chamber and head to the president’s desk for a veto.

In preparation for the potential intersection of the anniversary of the horrific terrorist attacks and a historic foreign policy vote, Republicans are sharpening their rhetorical barbs.

“Even the Ayatollah Khamenei said the Iranian parliament gets a vote on the nuke deal. It would be beyond irresponsible for Senate Democrats to block, by a filibuster, the vote,” Senate Majority Whip John Cornyn, (R-Texas) said in an interview on Tuesday.

But Cornyn also said that without an agreement between McConnell and Reid the Senate will likely vote next week.

Democrats say there’s a decent chance they would win that filibuster vote, but some Democrats are wary of blocking the resolution for fear of the political optics.

Sen. Joe Manchin (D-W.Va.) announced his opposition to the overall accord after souring on the possibility he'd be asked to filibuster a resolution of disapproval, even after signaling that he was preparing to back the deal.

In a Washington speech on Tuesday morning, Reid confidently declared that Obama's "agreement will stand.” But he was coy about whether he can hold his caucus together and block a resolution of disapproval from even reaching the president's desk.

"I don't have gut feelings. We'll have to wait and see how others will vote," Reid said as he left the Carnegie Endowment for International Peace, where he made a lengthy defense of the international deal that would lift some sanctions on Iran while scaling back their nuclear ambitions.

Other Democrats supporting the deal, like House Minority Leader Nancy Pelosi (D-Calif.) and Sen. Chris Murphy (D-Conn.) held events on Tuesday to herald the deal now that Democrats can clearly muster enough votes to sustain a veto of a resolution of disapproval.

Indeed, for backers of the deal there was much to celebrate as support materialized from Sens. Gary Peters of Michigan, Ron Wyden of Oregon and Richard Blumenthal of Connecticut. And Sen. Maria Cantwell (D-Wash.) added her support on Tuesday evening, saying "I'll support it in any way I can."

That backing brings support in the Senate for Obama's agreement to 42 Democrats, enough to deny the GOP a filibuster-proof majority of 60 votes. Notably, that apparently coordinated show of support emerged following Manchin's decision to vote against the resolution.

The last Republican hold-out, Sen. Susan Collins of Maine, formally sealed the Iran agreement’s partisan fate on Tuesday, announcing her opposition to the deal on Tuesday afternoon and ensuring that at least 58 senators will oppose the deal.