Republican efforts to stop the nuclear deal with Iran ended in failure Thursday, thwarted by unflinching Democratic support for President Obama's landmark accord and familiar GOP infighting.
With no clear strategy remaining to prevent the internationally backed deal, Republican leaders in Congress were left conducting largely symbolic votes that will register lawmakers' rejection of the deal but do nothing to upend it.
In the Senate, Republicans were met with a Democratic filibuster that blocked a resolution of disapproval, preventing it from being sent to the president's desk and depriving the GOP of a hoped-for veto showdown.
On a vote of 58 to 42, the Democratic and independent senators backing the agreement stopped Republicans from reaching the 60-vote threshold needed to advance the disapproval measure.
Four Democrats who opposed the deal joined all 54 Republicans. Senate Majority Leader Mitch McConnell (R-Ky.) vowed to try again.
"No amount of saying this is over makes it over," McConnell said, adding that if Democrats were so proud of the Iran deal, they should embrace the outcome. "Break out the champagne. Celebrate. Take credit for it. You own it." He set up a vote next week to "move past this procedural snag."
Obama praised the Senate for taking "an historic step forward" that will enable the U.S. to continue working with its partners to "prevent Iran from obtaining a nuclear weapon."
"Today, I am heartened that so many senators judged this deal on the merits, and am gratified by the strong support of lawmakers and citizens alike," the president said in a statement. "Going forward, we will turn to the critical work of implementing and verifying this deal so that Iran cannot pursue a nuclear weapon, while pursuing a foreign policy that leaves our country -- and the world -- a safer place."
A disapproval resolution also failed to come to a vote in the House, despite that chamber's larger Republican majority and different rules that made passage once appear assured.
Instead, GOP infighting forced a last-minute strategy shift on Wednesday and the House began voting Thursday on other measures designed to put Republicans on record against the deal. None are likely to become law.
The result over the next several days will be a slow-motion end to a debate that once gave Republicans an opportunity to challenge the White House on foreign policy but has now delivered the president a legacy-building achievement.
"We'll use every tool at our disposal to stop, slow and delay this agreement from being fully implemented," House Speaker John A. Boehner (R-Ohio) said Thursday.
But even as Republican lawmakers continued to resist the measure Thursday in hours of impassioned floor speeches in both houses, their confidence showed signs of erosion.
Congress gave itself until Sept. 17 to weigh in on the deal, which the United States, Britain, France, Germany, Russia and China negotiated with Iran. The goal of the accord is to limit Iran's nuclear activities in exchange for a lifting of economic sanctions.
Republican leaders are now looking past that deadline to the next opportunities to chisel away at support, including using the upcoming budget battle for fresh attacks on the Iran deal.
Vowing not to let up, Boehner said legal action to stop the president was "very possible," and he did not rule out trying to include Iran deal restrictions in the must-pass spending bill that is needed by Sept. 30 to keep the federal government from shutting down.
"We're pursuing, frankly, a number of options," Boehner said. "All options are on the table."
The speaker was taking a cue from Sen. Ted Cruz (R-Texas), a presidential candidate, who drafted a lengthy letter to GOP leadership Thursday, outlining steps needed for a legal fight against the deal.
Boehner faced an unexpected, if familiar, revolt this week when rank-and-file Republican lawmakers informed him they wanted a tougher approach than the disapproval resolution and would withhold their support for that effort.
A core group of conservative Republicans, aligned with a pro-Israel bloc led by Rep. Peter Roskam (R-Ill.), wanted to press the White House to release details about so-called side deals outlining the approach to inspecting Iran's nuclear installations. The administration maintains those technical arrangements, made between the International Atomic Energy Agency and Iran, are typically kept confidential.
Democrats, who endured their own struggles before supporting the president, ultimately gave strong backing to the bill.
"This is about peace," said Minority Leader Nancy Pelosi (D-San Francisco), siding with those who believe the agreement is the best chance to stop Iran from building a nuclear bomb and a better alternative to a military confrontation. "And we go forward."
The House was to vote later Thursday on a resolution finding that the administration was "not in compliance" with the terms of the congressional review because it failed to release the documents between Iran and the IAEA. On Friday, the House was expected to vote on a measure -- unlikely to pass -- to approve the Iran deal and another to prevent the lifting of sanctions until Jan. 21, 2017, after a new president is in the White House.
It is not clear whether McConnell would bring those measures for consideration in the Senate.
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