Senate Majority Leader Mitch McConnell leaves the Senate chamber on Sept. 8 after speaking out against President Obama's nuclear deal with Iran. Anadolu Agency AFP/Getty

If at first you don’t succeed in blocking a key White House priority—or at least embarrassing Democrats—try, try again.

So appears to be the Senate Republican mantra this week, as leaders once again brought up a resolution to signal formal disapproval of the president’s agreement with Iran to disable its nuclear program. After failing to pass a key 60-vote procedural hurdle last week, the resolution again failed Tuesday night.

Yet a third vote is expected before Thursday’s deadline for Congress to act on the deal, but Senate Majority Leader Mitch McConnell promised to add an amendment that could be a bitter pill for Democrats.

“If cloture is not invoked,” McConnell said before the failed cloture vote Tuesday night, “I will file on an amendment that would prevent the president from lifting sanctions until Iran meets two simple benchmarks: It must formally recognize Israel’s right to exist, and it must release the American citizens being held in Iranian custody.”

With a simple majority of support, McConnell could force a vote on the amendment as soon as Thursday, though 60 votes will be needed to pass it.

That puts Democratic supporters of the Iran deal in a tough position. One can already see the campaign ads in 2016 and beyond, warning that various Democratic senators voted against releasing American hostages in Iran and/or against Israel’s right to exist. Democrats are furious at what they cast as a purely political move by McConnell now that it is clear that he has lost the Iran fight.

“The Republican leader has threatened us: ‘Look, we lost and we’re going to make you suffer,’” Senate Minority Leader Harry Reid said on the floor Tuesday night.

McConnell's amendment promise is part of a strategy to force Democrats to own their support of the Iran deal, which he outlined in a press conference last week. "Every single one of [the Democrats] is going to want to try to trivialize this vote, try to convince their constituents that they still are really tough on Iran," McConnell said, telling reporters to expect Democrats to put out press releases, give speeches, and even introduce legislation attacking Iran to soften their position after voting to keep the deal.

"We'll not be turning the Senate floor into an opportunity for sort of therapeutic get-well exercises on behalf of all the Democrats who ended up voting for this bill, who are going to want to try to deceive their constituents into thinking that it really wasn't that important," he said last week.

McConnell said at the time that he would take up any "bill that legitimately goes after the Iranian regime" but would not allow it to hit the Senate floor until "it has enough cosponsors to override a presidential veto." That doesn't seem to be the case with McConnell's amendment.

The ending of this story is clear: Supporters of the Iran deal have not only sufficient support to prevent a final vote on the Iran disapproval resolution, but also plenty of votes to uphold a certain presidential veto on the deal itself. Despite disapproval from a majority of members of Congress in both chambers, including Republicans and some Democrats, Congress will tacitly approve of Obama’s deal with Iran.

The issue could ignite both parties’ bases, as Democrats and Republicans cast the other party as politically motivated on a foreign policy issue that is of major import to voters, the president’s legacy, and the nation’s future in general. But the scene also highlights Congress’ continued tendency to get bogged down in political and procedural fights that have turned off a majority of the American public.

Both parties cast the vote as political, arguing that members on the other side of the aisle are taking a serious issue too lightly.

“It’s part of a larger retreat to campaigning instead of engaging on this important issue—ad hominem attacks instead of serious debate, campaign one-liners instead of intellectual arguments, and simply ignoring reality when it becomes inconvenient,” McConnell said on the Senate floor Tuesday afternoon.

“This debate should not be about a president who will leave office in 16 months. It should be about where our country will be in 16 years,” McConnell added.

Clearly, the president is very much on the mind of both parties. Even if Democrats wave the white flag on cloture, the final vote count on the deal would be the same. All 100 members of the Senate have already staked out their positions on the deal and voted as such, so a reversal by any member at this point would be unheard of. Ad makers already have their eyes on the Democrats who voted against cloture, all of whom publicly support the deal. The only purpose of getting an up-or-down vote would be to force Obama to veto a disapproval resolution that has majority support in both chambers.

For Republicans, the continued Democratic filibuster of the Iran disapproval resolution lays bare a minority more interested in protecting a lame-duck president than legislating on perhaps the most significant foreign policy issue the Senate has dealt with since the Iraq War authorization. Every vote against the resolution (which would constitute a vote in favor of the deal), a presidential veto, and any votes upholding that veto, Republicans argue, all add to the Democratic Party’s ownership of the Iran deal—even despite some Democratic votes in opposition.

"I think accountability is really important,” Senate Majority Whip John Cornyn told reporters Tuesday. “I know they’re trying to say that it’s all over with, there’s nothing to see here, move on down the road, but this is the most serious national security vote we will have had at least since 2002 on the Authorization for the Use of Military Force, maybe even more [serious] since it involves nuclear weapons and a nuclear-arms race in the Middle East. So this is very important. And the idea that they can just brush this under the rug and move on from here—I think they underestimate the consequences of this both from a national security perspective and a political perspective of them owning this whole issue on a partisan basis."

Democrats, on the other hand, contend that the writing for the Iran deal has long been on the wall. The deal will go through, no matter how many times Republicans bring it up for a vote, and every member of the Senate has already had an opportunity—twice now—to go on the record either in support of or in opposition to the deal. The Senate should instead, they argue, get to work on a continuing resolution to fund the government before another government shutdown at the end of this month.

Reid called McConnell’s maneuvering on Tuesday to present the amendment a “charade,” adding: “The Republicans have lost; they’ve lost this measure, and they should move on to something else.”

“By the look of this week’s schedule, the Republican leader doesn’t seem to be in any hurry to avoid a government shutdown,” Reid said earlier Tuesday.

If the Senate sticks with Iran votes this week, it will have just seven legislative days left in the month to formulate and pass a continuing resolution while fending off stalling tactics from conservative members intent on including a measure that will defund Planned Parenthood.


Alex Rogers contributed to this article

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