In September, the House and Senate are planning to vote on bills demanding that the US back out of the P5+1 nuclear deal with Iran. The votes are expected to split almost entirely along party lines, and which Republicans initially expressed confidence at getting enough Democrats to override a presidential veto, that seems a remote possibility at best.
31 senators have already endorsed the deal, and only 34 are needed to enforce a presidential veto. The 13 remaining undecided Democrats, however, could give them a shot at filibustering against even having a vote, with 60 votes needed to block a filibuster and force a vote, and by extension a veto.
Either way, the P5+1 deal seems safe, but Republicans are now seeing forcing a veto as at least a partial victory, and are threatening huge political consequences if the Democrats manage the filibuster, saying that the Democrats would be “denying the people a vote” on the matter.
The White House is said to be keen to avoid having to veto a resolution against the deal, and would prefer it not to come up. Even if a filibuster precludes the Senate vote and the need for a veto, Republicans are suggesting the House might vote anyhow, though such a vote would be meaningless.
With tensions of millions of dollars of AIPAC lobbying going into trying to kill the deal, a lot of Congressmen are hoping to prove their loyalty to the lobbyists by voting against the pact, and they seem horrified that they might lose that opportunity if there is no vote.