Iran letter could backfire, GOP dissenters say. http://t.co/O6hsUnZAzq

— POLITICO (@politico) March 10, 2015

With Republicans needing significant Democratic support to achieve their goal of derailing the talks — or at least altering the emerging deal — some senators said Cotton’s effort could backfire by injecting excessive partisanship into the debate over how best to prevent a nuclear-armed Iran.

Senate Foreign Relations Committee Chairman Bob Corker said he was approached to sign the letter by Cotton, a Republican from Arkansas, but he concluded it might set back his ultimate goal: veto-proof support for a bill he has sponsored requiring a congressional vote to approve or reject an Iran deal.