WASHINGTON – Philadelphia-area Senators split on the international nuclear deal with Iran Thursday, with four voting in support of the agreement – and helping to ensure it will go into force -- and two voting to kill it.

Sens. Pat Toomey and Robert Menendez (D., N.J.) voted for a resolution to stop the pact, though that plan fell short of the votes it needed, handing President Obama a major victory on international policy and ending any realistic chance Congress had of stopping the accord.

Sens. Bob Casey (D., Pa.), Cory Booker (D., N.J.), Tom Carper (D., Del.) and Chris Coons (D., Del.) all voted to block the Senate resolution and allow the nuclear agreement to take effect. The outcome had been expected for days.

Menendez was one of just four Democrats to oppose the deal. Every senator had announced their positions before Thursday's vote.

A majority of the Senate – 58, including every Republican – wants to stop the agreement, but their resolution was blocked by 42 Democrats who support the deal. Under Senate rules, 60 votes are needed to overcome procedural hurdles and advance legislation.

The Democratic blockade, using a tactic Republicans long employed and that Democrats criticized, spares Obama from having to veto Congress' disapproval of one of his signature achievements.

The House is planning its own votes on the deal, though any resolution to stop the agreement now appears dead, with no path to get through the Senate. Senate Republicans, however, plan another vote next week, hoping a weekend of pressure changes some senators' minds.

Opponents argued that the deal is too weak, and will open the door for a nuclear Iran, threatening the U.S. and Israel.

The agreement "failed to achieve the one thing it set out to achieve – it failed to stop Iran from becoming a nuclear weapons state at a time of its choosing," Menendez said in a floor speech before the vote. "In fact, it authorizes and supports the very road map Iran will need to arrive at its target."

Local supporters of the deal anguished over the details of the agreement, but said it is the best of several bad options, and better than walking away from an international agreement that other world powers – Britain, China, France Germany and Russia – have agreed to and plan to put into force. They have argued that the deal will constrain Iran's nuclear ambitions for the next 10 to 15 years, improve oversight of its nuclear facilities and push back its "break out" time if it tried to build a nuclear weapon from months to around a year.

"Most Iranians want a better relationship with America and the world," Carper said on the Senate floor. "This new generation of Iranians are ready to take 'yes' for an answer. I think we should, too. This is a good deal for America and our allies."

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