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Republican leaders vowed Wednesday to press forward with a rigorous debate over the merits of the deal

Moving forward, Republicans say they want to pass new sanctions on Iran

Washington CNN  — 

Congressional Republicans faced a significant, but expected, setback Wednesday when Democrats secured the 34 Senate votes they need to sustain a presidential veto of GOP legislation that would scuttle the Iran nuclear agreement.

Still, Republican leaders vowed to press forward with a rigorous debate over the merits of the deal and are looking at House and Senate votes as early as next week to show that while President Barack Obama is now assured to get his Iran deal, a majority of lawmakers still oppose it.

The top Senate Republican leader conceded that his party’s best hope now to unravel the deal is to elect a new president in 2016 who would dismantle it.

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“While the President may be able to sustain a veto with the tepid, restricted and partisan support of one third of one house of Congress over Americans’ bipartisan opposition, it will require a bipartisan Congress to strengthen our defenses in the Persian Gulf and to stand up to the inevitable Iranian violations of the agreement that will need to be addressed after he has left office,” Senate Majority Leader Mitch McConnell said in a statement issued shortly after Sen. Barbara Mikulski, D-Maryland, became the 34th Democrat to announce support for the deal.

“And because it is not a treaty, it can and should be revisited by our next president,” he said.

House Speaker John Boehner was equally blunt. His spokesman stressed that despite the administration’s ability to get enough votes to allow the deal to stand, it still wasn’t broadly embraced and suggested roadblocks would be ahead.

“Forcing a bad deal over the objections of the American people and a majority in Congress is no win for President Obama,” Boehner’s spokesman Cory Fritz said. “The White House may have convinced just enough Democrats to back an agreement that legitimizes Iran’s nuclear program, trusts the regime to self-inspect and offers amnesty to terrorists, but this deal is far from being implemented.”

Wednesday afternoon, House Minority Leader Nancy Pelosi expressed confidence that House Democrats would be able to sustain Obama’s veto. In the event the GOP-led House and Senate both pass resolutions to block the deal, the House would vote first on a veto override.

One recent CNN poll showed that a majority of Americans, 56%, want Congress to reject the deal, although other polls show majority support for the agreement.

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To date, only two Senate Democrats, Chuck Schumer of New York and Robert Menendez of New Jersey, have come out against the bill and nine remain unannounced. Democratic Senate leaders hope to get another seven Democrats to back the deal, which would allow them to filibuster, or block, the disapproval resolution from coming to a final vote. Republicans are trying to prevent that from happening so they can get a formal vote on the agreement. But if Democrats are able to filibuster in the Senate, House Republicans could move quickly to pass the disapproval resolution to show there is a majority in the House that wants to derail the deal. But the deadline for a vote, Sept. 17, isn’t until the following week.

Senate votes are also likely next week, although McConnell hasn’t announced it. Scheduling votes the week of the deadline is complicated because of a Jewish holiday early in the week and the second Republican presidential debate is on Wednesday, September 16, in California.

Senate Republicans running for president, who are likely to make some of the biggest noise during the upcoming floor debate, were quick to condemn the expected implementation of the agreement.

“The Iranians have now secured enough votes in the Senate to ensure they have a pathway to a bomb, the missile to deliver it, and the money to pay for it,” said Sen. Lindsey Graham of South Carolina. “The only reason the Ayatollah and his henchman aren’t dancing in the streets of Tehran is they don’t believe in dancing.”

Republicans on Capitol Hill knew all along that simple math made their effort to block the deal an uphill battle from the beginning. The Iran Review Act, which was the bipartisan compromise legislation giving Congress the ability to weigh in on the deal, gave Obama the upper hand because he only needed to get enough fellow Democrats to stand with him to uphold his veto of a Republican resolution to block the deal.

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Many conservative Republicans on Capitol Hill griped that their leaders had signed onto a structurally flawed mechanism because the President would be able to clear the deal with just 34 Democratic votes, the number required by the Constitution to sustain a veto. But GOP leaders were forced to accept the bill as the only way to get a formal review of the agreement, which the White House was prepared to implement without the input of Congress.

Moving forward, Republicans say they want to pass new sanctions on Iran and it’s likely this fall that GOP leaders will want to debate the issue because they view it as a winning issue in the 2016 election. But any effort while Obama is in office would surely be vetoed.

And Sen. Marco Rubio of Florida, a Republican who is running for president, conceded the fight was over for now in Congress.

“When I’m President of the United States, we will re-impose those sanctions on day one and I will go to Congress and ask them to even increase those sanctions more,” he said.