At his presser today, President Obama reiterated his opposition to Congress passing any bill now imposing new sanctions on Iran. He repeated that his goal is to prevent Iran from gaining nuclear weapons, and said he would prefer to accomplish this through diplomacy, adding: “I would think that would be the preference on Capitol Hill.”

Translation: By imperiling the prospect of a long term diplomatic solution curbing Iran’s nuclear program, Congress would be making war more likely.

I’m told that Senator Barbara Boxer, a leading opponent of a new sanctions bill and a senior member of the Foreign Relations Committee, is working behind the scenes to persuade other Senate Democrats to oppose against any such bill if it comes up for a vote.

“I’m definitely talking to my colleagues and making the case that a rush to a new sanctions bill could disrupt these sensitive negotiations with Iran,” Boxer says, in a statement emailed my way.

That raises an interesting question: What if this bill comes to a vote and goes down in the Senate?

Already, Democrats are divided on the push for a new sanctions bill. Senators Robert Menendez and Chuck Schumer are leading the push for the bill, and they have been joined by 11 other Democratic Senators. On the other hand, 10 Dem Senators — all committee chairs — have come out against the sanctions bill, arguing in a letter to Harry Reid that “new sanctions would play into the hands of those in Iran who are most eager to see the negotiations fail.”

That leaves at least 30 Dem Senators who may be up for grabs.

This means that, in addition to the organizing that Boxer is undertaking, you’re all but certain to see more pressure be brought to bear on Democrats to back off of Congressional action right now. (There is also pressure on them to support the new sanctions bill, but the organizing that’s taking place against it is getting less attention.) As HuffPo reported yesterday, liberal groups like MoveOn and CREDO are already pillorying senators Menendez and Schumer for undermining the negotiations and playing into GOP efforts to fracture Dem unity on Iran. Pressure will probably be brought to bear on undecided Dems, too.

Senate aides say they are not ready to predict whether the Iran sanctions bill will or won’t pass. Right now 13 Republicans have signed on to the Menendez-Schumer bill. But you could conceivably see Republican Senators like Rand Paul and Mike Lee, who have been more suspicious of the use of American power abroad than neocons or GOP internationalists have traditionally been, come out against the bill. I’ve asked Senator Paul’s office where he stands and haven’t received an answer. What will he say?

There will also be tremendous pressure brought to bear from both sides on Harry Reid, who has yet to say whether he’ll allow it to come to a vote. If more Dems come out against the bill, it will become harder for him to bring it to a vote.

It remains very possible that the bill will pass the Senate, and if the White House is right, that could imperil the chances of a long term diplomatic breakthrough. But it’s also possible the bill will fail, which would be a major rebuke to the hawks.


UPDATE: Chuck Schumer responds to the President:

“Many of us believe that ratcheting up sanctions, not reducing sanctions, is the best way to produce peace and get Iran to forego a nuclear weapon.”