The top Republican is Illinois's Mark Kirk, a consistent leader on the issue. He is joined with John McCain, Lindsay Graham and Kelly Ayotte, who work together on many foreign policy issues, and prominent freshmen Marco Rubio and Ted Cruz.
The Senate bill would impose increased sanctions six months after the Geneva agreement goes into effect unless Iran agreed to certain specified conditions. Top House leaders, including Foreign Affairs Committee Chairman Ed Royce and ranking Democrat Elliot Engel, seem ready to pass similar or identical legislation.
Backers argue that it would give administration negotiators leverage on Iran to gain agreement on objectives the president has often said he seeks.
The administration doesn't agree. White House Press Secretary Jay Carney said flatly last week that the president would veto the bill. Administration lobbyists have been beseeching Democrats not to back it.
Their arguments don't track with their stated objectives. They say they fear that Iran will walk out of negotiations if more sanctions are threatened. But tough sanctions are what brought them to the table.
They say new sanctions could be passed later. But the Senate bill doesn't put them into effect until later.
They argue that Iran won't ever agree to end uranium enrichment. But the whole point of sanctions is to get the mullah regime to do something it doesn't want to do. If getting to yes were the only objective, we might as well just accept a nuclear-armed Iran.
It's not clear that the sanctions bill will ever get to the floor of the Senate. Even high-caliber sponsors such as Menendez and Schumer may be less persuasive with Harry Reid than calls from the White House.
But it is clear that there are majorities -- solid bipartisan majorities -- in both houses for additional pressure on Iran and for insistence on a final agreement that ends the threat of Iranian nukes rather than one that puts it off for another day.
In this regard Congress seems to be reflecting the will of the American people. Will the administration listen?
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