Today the Senate passed a bill that would give Congress the authority to review the emerging nuclear deal with Iran. The bill—and the vote—was controversial, with many Republicans arguing against final passage; those who opposed sending the bill to the House argued that it was not strong enough, and would not provide a big enough buffer between the Obama Administration, and a nuclear Iran.

Fox News explains why Senate leadership pushed so hard for the passage of the bill:

Senate Majority Leader Mitch McConnell, R-Ky., said the bill “offers the best chance for our constituents through the Congress they elect to weigh in on the White House negotiations with Iran.”

Added Sen. Bob Corker, R-Tenn., chairman of the Foreign Relations Committee: “No bill. No review.”

The legislation would bar Obama from waiving congressional sanctions for at least 30 days while lawmakers examine any final deal. The bill would stipulate that if senators disapprove of the deal, Obama would lose his current power to waive certain economic penalties Congress has imposed on Iran.

The bill would require Congress to pass a resolution of disapproval to reject the deal, an action that Obama almost certainly would veto. Congress then would have to muster votes from two-thirds of each chamber to override the veto.

In the House, about 150 Democrats — enough to sustain a veto — wrote the president to express their strong support for the nuclear negotiations with Iran.

Push they did—and it wasn’t easy. The White House threatened to veto the bill, and a series of amendments sponsored by various Republicans put final passage at risk. One of those amendments—the most controversial, in my opinion, at least as far as the need for bipartisan approval is concerned—would have required Tehran to recognize the right of Israel to exist before any deal could be approved. Some of the amendments (including the Israel amendment) made sense, but had they succeeded, would have scuttled the bill, putting in jeopardy even a slight delay to any nuclear deal the Administration comes up with.

The bill passed 98-1, with only Arkansas Senator Tom Cotton objecting.

In a statement following the bill’s passage Thursday afternoon, Cotton said the Iran deal should be submitted as a treaty requiring a two-thirds majority vote in the Senate.

“President Obama wants to reverse this rule, requiring opponents to get a two-thirds vote to stop his dangerous deal,” Cotton said. “But Congress should not accept this usurpation, nor allow the president any grounds to claim that Congress blessed his nuclear deal. I will work with Republicans and Democrats to stop a dangerous deal that would put Iran on the path to obtaining a nuclear weapon.”

Welcome to round 4,576 of “do we pass a backstop, or hold out for a bulletproof vest?”

The bill will now move over to the House; it’s expected to pass there, but there’s no telling what might happen once it hits the President’s desk.