The Hill – August 18, 2015 – Sen. Bob Menendez on Tuesday announced his opposition to President Obama’s nuclear deal with Iran, becoming the second Senate Democrat to defy the White House on a top foreign policy priority.

“I have looked into my own soul and my devotion to principle may once again lead me to an unpopular course, but if Iran is to acquire a nuclear bomb, it will not have my name on it,” Menendez (D-N.J.) said in a speech Tuesday afternoon, according prepared remarks.

“It is for these reasons that I will vote to disapprove the agreement and, if called upon, would vote to override a veto,” Menendez said.

The decision, though expected, strikes another blow to the administration’s efforts to rally support for the deal as Congress prepares to vote on it in September.

The president, although on vacation, has been reportedly calling members of Congress during the recess break.

The president’s push comes amid furious lobbying by pro- and anti-deal groups targeting undecided Democrats.

Sen. Charles Schumer (D-N.Y.), the Senate’s third-ranking Democrat, announced his opposition on Aug. 6.

Republicans now only need four more Democratic defections to pass a measure disapproving of the deal in the Senate, though they would need several more to override Obama’s expected veto of any such legislation.  

Menendez, a senior member of the Foreign Relations Committee, has been perhaps the most vocal critic of Iran in the Senate, and a leading supporter of maintaining sanctions on the nation, in case diplomacy failed.

In hearings and in statements, he has been critical of the deal, saying, “the bottom line is: The deal doesn’t end Iran’s nuclear program — it preserves it.”

Under the Iran Nuclear Agreement Review Act, which Menendez co-sponsored, Congress has 60 days to review the nuclear deal, and pass a resolution of approval, disapproval or take no action.

Republicans are planning to introduce a resolution of disapproval, aiming to kill the deal negotiated by six nations with Iran.

With Menendez’s support, Senate Republicans now have 56 of the 60 votes they’ll need for a filibuster-proof majority to pass the resolution.

However, the president has said he would veto such a resolution, which would force Republicans to gather two-thirds of lawmakers to override the veto.

So far, the administration has 21 of the 34 Democrats supporters it’ll need to sustain its veto, according to The Hill’s whip list.

Twenty-three Senate Democrats are still undecided.

The odds of bipartisan support for the deal in the Senate got longer last week after Sen. Jeff Flake (R-Ariz.) announced his opposition.