Jason Reed / Reuters

According to Bob Dole, either the “shortest distance” or the “most dangerous place” in Washington, D.C. “is between Chuck Schumer and a television camera.” The senior senator from New York and minority-leader-in-waiting has such a  penchant for bombast that it seems noteworthy when he says something understated.

His statement on the nuclear agreement struck between Iran and six world powers on Tuesday is one shining example:

Over the coming days, I intend to go through this agreement with a fine-tooth comb, speak with administration officials, and hear from experts on all sides. I supported legislation ensuring that Congress would have time and space to review the deal, and now we must use it well. Supporting or opposing this agreement is not a decision to be made lightly, and I plan to carefully study the agreement before making an informed decision.

That’s a far cry from the sweeping condemnations delivered by Republican legislators and presidential candidates or the endorsements of his own party leader and some of its left-leaning members. From his perch at the vanguard of the American center-left, Schumer’s pro-Israel and foreign-policy bona fides make him the crucial figure in the congressional fight over the nuclear deal.

“If Schumer comes out and says, ‘I looked at the bill and studied its details and think it’s a good deal and will stop Iran from getting weapons,’ there will be zero hope of overriding an Obama veto,” Noah Pollak, the executive director of the Emergency Committee for Israel, told The Hill on Tuesday.

Over at Newsweek, Jonathan Broder puts Schumer atop a list of influential Democrats that also includes “Senator Ben Cardin of Maryland, the ranking member of the Senate Foreign Relations Committee; and House appropriator Debbie Wasserman-Schultz of Florida,” whose positions on the accord could direct a tide of Democratic votes.

Before the particulars of the deal had even seen the light of day, Senator Lindsey Graham was already pushing Schumer to commit to killing the agreement. “Chuck Schumer is supposed to be the guardian of Israel. He goes around everywhere and says, ‘My name is Schumer. It means guardian of Israel,’” Graham said on MSNBC’s Morning Joe on Tuesday. “Well, if you care about Israel, you will not put her in this box. If you care about the United States, you will not allow our chief antagonist to become a nuclear threshold nation guaranteed in nature with no restrictions for them to go beyond that.”

The pressure isn’t just coming from across the aisle, but also from within the tribe. My colleague Jeffrey Goldberg noted on Twitter that an alumni group for the Birthright organization emailed its members with instructions to call Schumer and ask him to reject the deal. That’s not to mention Schumer’s heavily-Jewish constituent and support base in New York.

So will he or won’t he? Back in April, Schumer sided with his Republican colleagues in a call to put a potential nuclear deal to a vote in Congress. Hillary Clinton’s endorsement of the deal may have given Schumer some breathing room if he’s angling to support it. Bernie Sanders, for what it’s worth, was more enthusiastic in his approval. For now, it seems unlikely that 13 Democratic members of the Senate will defect. But if one person can lead them, particularly with 60 days for the controversial accord to be reviewed, it’s Schumer.

Tuesday’s agreement didn’t only put Democrats in a bind. Senator Rand Paul, who is making a run for the White House as the most dovish candidate in the Republican primary field, didn’t release a statement until much later in the day.

In it, Paul split the difference, saying he would oppose the nuclear deal, but he “continue[s] to believe that negotiations are preferable to war,” a statement that set him apart from the bellicose reactions of much of the Republican field. Writing in The Atlantic on Tuesday, David Frum declared Paul’s candidacy to be “over.”

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