Three more senators announced their support for the Iran nuclear deal Tuesday, giving Democrats enough manpower to prevent Senate Republicans from passing a resolution disapproving of the accord and forcing President Obama to veto it.
Sen. Ron Wyden, D-Oregon, Sen. Gary Peters, D-Michigan, and Sen. Richard Blumenthal, D-Connecticut, brought the total number of Democratic senators supporting the deal to 41. Their support means that Democrats could filibuster the bill blocking the deal Republicans have promised, but Democratic leader Harry Reid, D-Nevada, said Tuesday morning that's not his goal.
"I hope we can avoid the usual and unnecessary procedural hurdles. Democrats have already agreed to forgo our opportunity to filibuster, and I've offered Leader McConnell the chance to go straight to a vote on passage of the resolution," Reid said according to his prepared remarks for a speech at the Carnegie Endowment.
Reid did say he will insist that Republicans get 60 votes if they want to pass the resolution of disapproval. With 41 senators in support of the deal, Republicans can get a maximum of 59 votes to block the nuclear agreement.
In a statement announcing his support, Blumenthal wrote, "While this is not the agreement I would have accepted at the negotiating table, it is better than no deal at all. And it can be made even better through unilateral American action and collaboration with our European allies. He said the decision was "a difficult one for me," but he believes it is the best way to prevent Iran from gaining a nuclear weapon. He also said blocking the deal is "fraught with unacceptable risk" because U.S. allies have indicated they will not return to the negotiating table.
Peters said he will "reluctantly" vote against a bill blocking the agreement despite several concerns, including that the deal allows Iran to continue enriching uranium.
"Despite my serious concerns with this agreement, I have unfortunately become convinced that we are faced with no viable alternative. I have met with representatives for each of our negotiating partners, whom have all stated that they will not return to the negotiating table if Congress rejects this deal," Peters said in a statement. "Further, I believe a rejection of this agreement will damage the international credibility of the United States, and that attempting to go it alone and implement unilateral sanctions without a coalition of nations will only weaken our standing."
Lawmakers are beginning formal consideration of the deal Tuesday as they return to Washington, and are expected to vote sometime before Sept. 17.
While President Obama secured a crucial victory Tuesday morning, he also lost the support of Sen. Joe Manchin, D-West Virginia, who had said on CBS' "Face the Nation" in July that he was leaning strongly toward approving the deal.
"I do not believe that supporting this deal will prevent Iran from eventually acquiring a nuclear weapon or continuing to be a leading sponsor of terrorism against Americans and our allies around the world," he said in a statement.
He joins three other Democratic senators - Chuck Schumer of New York, Robert Menendez of New Jersey and Ben Cardin of Maryland - who are also voting to block the deal.
The lobbying efforts to sway lawmakers have been intense since the final deal was unveiled in July. Israeli Prime Minister Benjamin Netanyahu and various pro-Israel lobbying groups and committees in the U.S., such as the American Israel Public Affairs Committee, have mounted a vigorous, multi-million dollar advertising campaign to build public opposition to the agreement.
CBS News Correspondent Nancy Cordes and CBS Radio News Congressional Correspondent Steven Portnoy contributed to this story.