WASHINGTON — One day, you have Capitol Hill's most rare currency: bipartisan support. A few days later, your agenda is teetering on the brink. Just ask Senate Foreign Relations Committee Chairman Bob Corker.
Suddenly, the Tennessee Republican must deal with an embattled Democratic partner, as well as a miles-wide — and growing — rift on Iran between 47 of his Republican mates and the Obama White House.
Corker took the high-profile gavel in January at what seemed a fortuitous moment. There was support from Republicans and Democrats on issues the committee had been working on for some time: a bill requiring congressional approval of any deal on Iran's nuclear program and another effort to craft an authorization of the use of military force (AUMF) for the Islamic State conflict.
"We've got to show people that we can deal with a serious issue in a serious way," Senate Foreign Relations Committee member Tim Kaine, D-Va., told CongressWatch Tuesday. "And we've got two real tough ones on the table right now: Iran and the ISIL AUMF. And the world will either benefit or be disadvantaged by an Iran deal or no deal … They need to know we're going to look at it seriously."

Those tough issues only got politically tougher since Congress adjourned early last Wednesday ahead of a Washington snow storm.
Senate Democrats the next day forced Majority Leader Mitch McConnell, R-Ky., to delay a vote on a bill requiring the Senate to approve any Iran deal. On Friday, the Justice Department confirmed reports that Corker's wing man on the panel, Ranking Member Bob Menendez, D-N.J., likely will soon face federal corruption charges.
"I do think" recent events "make a number of my colleagues who I think would sign on to the Corker-Menendez bill … now like 'Well, I kind of agree on the substance, but isn't the Senate showing they can't take this up in a rational, bipartisan way?'," Kaine said.
"I'm trying to convince them to focus on the substance," he added, "but it gets harder and harder when people are pulling stunts like this."
Like other Democrats, Kaine is pinning much of the blame on freshman Sen. Tom Cotton, R-Ark., and 46 other Senate Republicans who on Monday wrote a letter to Iranian officials saying they would not support the rumored substance of an alleged deal on their nuclear program.
"I was flabbergasted," Senate Armed Services Committee member Bill Nelson, D-Fla., said of the GOP letter.

"If that can happen these days, then I can't predict anything about the AUMF," Nelson told reporters. "What the problem is is the partisanship is being injected into the foreign policy and national security interests of this country.
"What it is sends is a message to the rest of the world that we are not united," he said. "I think the letter makes it a lot more difficult to negotiate successfully a deal to keep them from developing a nuclear weapon.
Notably, Corker opted against signing the Cotton letter.
He told reporters Tuesday that he views his role as Foreign Relations Committee chairman as leading a process "to get us to an outcome" on issues like the potential Iran deal.
"I didn't think the letter was something that would get us to an outcome," Corker said.
Asked if he is worried the letter will sink his agenda, Corker replied: "I'm not."
He then criticized the White House for stating publicly that they see no role for Congress on authorizing an accord with Tehran. "What I don't understand is [why] the White House has pushed back so hard."
Senate Armed Services Committee Chairman John McCain, R-Ariz., was last session a member of the Foreign Relations panel when Menendez was still the chairman.
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"I appreciate his leadership," McCain said, adding of the coming corruption charges: "And I made no judgement."
McCain seemed optimistic that the efforts can get back on track.
"I think, in the end, Democrats will do what's best for this institution and the country," he said.
Still, the familiar aftertaste of partisanship lingered in some palates.
"I am saddened that we have become so divided that almost half of the senate," Nelson said, "are trying so obviously a partisan thing when matters of war and peace are at stake."
email: jbennett@defensenews.com
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