Days after Sen. Robert Menendez was indicted on federal corruption charges, Senate Minority Leader Harry Reid was on the phone with the man who would replace him as the ranking member of the Senate Foreign Relations Committee: Ben Cardin of Maryland.

The delicate negotiations in Congress over how to respond to the Iran nuclear framework were coming to a head — and Democrats were all over the map. Liberals were pushing Democrats to stand behind the White House, and Israel hawks like Sen. Chuck Schumer (D-N.Y.) were prepared to break from President Barack Obama.


But there would be no ramp-up time for Cardin: Reid made crystal clear the Maryland senator would be calling the shots.

“Every team has one quarterback,” Reid told Cardin, according to sources familiar with the call. “And you’re it.”

The low-key Cardin engaged in a furious round of negotiations with gregarious Senate Foreign Relations Committee Chairman Bob Corker, prompting something that was once viewed as almost unthinkable: a bipartisan deal for Congress to review an Iran nuclear deal — with the blessing of President Barack Obama and House Minority Leader Nancy Pelosi.

As talks intensified through the weekend, Cardin served as a liaison between Corker and the White House, relaying concerns voiced by the president’s chief of staff, Denis McDonough, and reassuring Obama about the emerging deal along the way. Meanwhile, Corker, a blunt-spoken Tennessee Republican with a heavy drawl, was burning up the phones over the two-week congressional recess, keeping at bay presidential hopefuls like Florida Sen. Marco Rubio as he sought to find a middle ground on the highly charged issue.

The talks carried into meetings Monday night in the Dirksen Senate Office Building and continued Tuesday with classified briefings with top Cabinet officials before culminating with a 19-0 vote in the Foreign Relations Committee. The vote united two Republican presidential hopefuls with divergent views on foreign policy — Rubio and Rand Paul of Kentucky — along with staunch liberals like Barbara Boxer of California and Chris Murphy of Connecticut.

The Cardin-Corker détente over a centerpiece of Obama’s foreign policy legacy showed that sometimes the best way for congressional leaders to get a deal on a contentious issue is to stay out of it.

“Sen. Reid made it very clear to me that I was responsible and in charge, and he said, there’s one leader in this issue, and I was the person,” Cardin said in an interview Tuesday. “He gave me complete authority to negotiate.”

The final legislation would give Congress a month to review a final multilateral deal with Iran and allow lawmakers to block Obama from lifting legislative sanctions that have crippled Iran’s economy. The bill is set to head to the Senate floor as soon as next week.

On Tuesday morning, the mood was tense during a classified briefing between senior administration officials and senators. Energy Secretary Ernest Moniz tried to lighten the mood by cracking some jokes, but senators sat silently, leading to awkward moments, attendees said. Just hours before the committee vote, Secretary of State John Kerry had been lobbying against the bill during the briefing, lawmakers said.

But sensing the administration’s opposition to a congressional role in reviewing the deal was a losing hand, the White House shifted its position later Tuesday and announced that Obama would sign the bill.

“The secretary of state was continuing to push back against our role,” Corker recounted after the vote. “They came to the right place, ultimately. Right before a 19-0 vote in the committee.”

Getting to this point took delicate maneuvering by both Cardin and Corker. For one, Democrats needed to figure out a way around the Menendez issue. After being indicted on federal bribery charges, the New Jersey Democrat agreed to step down as ranking member, though he tried to remain engaged in the congressional-review bill. Cardin kept Menendez’s staff in charge of the negotiations, but the senators’ dramatically different styles — especially when it came to their relationship with the White House — were apparent to everyone involved in the talks.

When Menendez said earlier this year that the administration was using some of the same talking points that Tehran was employing, Cardin was reiterating that he wouldn’t support anything that hamstrung the president’s ability to negotiate. And Menendez had privately sparred with the president at the Democrats’ retreat in Baltimore in January, while Cardin was on the receiving end of phone calls from Obama on the Iran talks multiple times this year.

“Menendez has been a strong, active, even at times strident voice on behalf of Israel’s security and has been an effective and persistent critic of the administration’s conduct of negotiations,” said Sen. Chris Coons (D-Del.), a committee member who traveled to Africa during the congressional recess and was on the phone virtually every night with Cardin and Corker. “Cardin has consulted closely with the White House about their concerns.”

Menendez insisted Tuesday he was privy to intelligence on the Iran bill negotiations as they took shape — “I’m playing just about every role I would have for all intents and purposes,” he said — but it was Cardin who was engaged in back-channel discussions with Kerry, McDonough, Moniz — and Obama himself.

“They were very candid about their views, very clear on their priorities, and very clear on how they would like to see things proceed,” Cardin said of the president and his senior aides. “Sen. Corker and I were very clear on each other: We started with the premise that we wanted the bill to work.”

Corker, an affable former Chattanooga mayor and owner of successful real estate companies, showed his dexterity throughout the course of the talks. Last summer, only Republicans were backing the bill, but Corker set out to build a veto-proof majority.

Corker changed the structure of the bill from allowing Congress to reject a deal with Iran to allowing lawmakers to reject the lifting of legislative sanctions, which will be key to any final deal with Tehran. That change brought aboard a number of Democrats like Tim Kaine of Virginia, who were persuaded by Corker’s constitutional argument, and in February they introduced a newly revised bipartisan version.

But that wasn’t enough. The president still threatened to veto the plan, and many undecided Democrats demanded additional changes, including Cardin, a 71-year-old former House member. Cardin and Corker spoke frequently over the past 10 days, each playing middleman for the respective caucuses.

They agreed to kill a provision requiring the president to certify that Iran does not support terrorists against the United States, language viewed as outside the scope of the Iran negotiations, though the bill requires reports from the administration. They clarified that the bill does not explicitly require Congress to approve or reject a deal.

They also halved the 60-day congressional review period to 30 days, reflecting concerns that the bill would make it impossible to strike a deal with Iran, which wants economic sanctions lifted quickly. Additional review time can be tacked on if Congress passes a disapproval resolution and Obama vetoes it, or if no deal is struck by July 9.

By the time Cardin briefed Democratic leaders Monday evening in Reid’s office, the leadership team was stunned at how far the Maryland Democrat had come. Schumer, a fierce skeptic of the Iran deal, praised Cardin as well, attendees said.

At meetings between Jewish leaders and Obama at the White House on Monday, the president signaled that the bill was moving in a direction he could support. In one session, questions emerged over inspections and monitoring Iran’s behavior.

“They had answers, but I don’t think anybody thought they were good answers,” said one person in the meeting, referring to White House responses.

But as Cardin was moving the bill to the left, Corker was working aggressively to keep Republicans at bay. He spoke extensively to Ron Johnson of Wisconsin, who wanted the Iran deal to win approval by two-thirds of the Senate, much like a treaty. Corker tried to appease concerns of Johnny Isakson of Georgia, who was seeking compensation for American victims of the 1979 Iranian hostage crisis. In the Senate basement, he had a lengthy conversation with Sen. Cory Gardner (R-Colo.) about eliminating a certification requirement, a concession that angered some Republicans. And the Tennessean tried to work with Rubio, who sought to push pro-Israel language that could have scuttled the nuclear deal.

Corker was on the phone extensively with Rubio and a like-minded conservative, Jim Risch of Idaho, both committee members. At an event with Rubio donors in Boise earlier this month, Risch and Rubio huddled privately to discuss their concerns over the proposal and relayed them to Corker.

Still, despite the changes to mollify Democrats, Rubio said that was the only way to get a bill done.

“We need … to make it veto-proof, and that would require us to make some changes that perhaps aren’t ones we would advocate for,” Rubio said in an interview Tuesday. “We’re trying to get to an end result on a very important issue.”

Edward-Isaac Dovere contributed to this report.