Chuck Schumer is getting an earful from opponents of the Iran nuclear deal.

More than 10,000 phone calls have flooded his office line the past two weeks, organized by a group looking to kill the deal. Another group has dropped seven figures on TV in New York City to pressure Schumer and other lawmakers to vote against the plan. The powerful American Israel Public Affairs Committee has put its muscle behind an effort to lobby the New Yorker against it.


And Dov Hikind, a state assemblyman from Brooklyn, was arrested for disorderly conduct while protesting the deal outside Schumer’s office.

People who have spoken with the senior New York senator believe the pressure campaign is having an effect: They say there is a growing sense inside and outside the Capitol that Schumer will vote against the deal when the Senate considers it in September. The bigger question many have now is this: How hard will he push against it?

Schumer is one of about 15 Democratic senators who will decide the fate of President Barack Obama’s Iran nuclear deal in Congress. The president can afford to lose no more than a dozen Democrats on the Senate floor, and as the next Democratic leader, Schumer may be the most critical of them all.

In an interview with POLITICO, Schumer insisted he’s still weighing his vote. He said he would decide based on the merits of the deal, not lobbying from either side.

“I haven’t made up my mind,” said Schumer, who is in line to be the first Jewish Senate leader next Congress. “There are expectations all over the lot. I’m doing what I’m always doing when I have a very difficult decision: Learning it carefully and giving it my best shot, doing what I think is right. I’m not going to let pressure or politics or party get in the way of that.”

He wouldn’t say if he would forcefully advocate his position once he makes his stance clear.

“I’ve got to first decide how I’m voting,” Schumer said.

Opponents have been much louder than supporters. If that trend continues over the break at town hall meetings, it will only amplify pressure on swing Democrats to vote against the deal.

Sen. Chris Coons, who was personally lobbied by President Barack Obama and national security adviser Susan Rice to back the deal during a trip to Africa in July, said the view of the accord was about evenly split in his home state of Delaware in the first few days after the announcement. But the Democrat now says telephone calls against the deal outnumber those in favor by 10-to-1 in his state, an avalanche of opposition he has no choice but to listen to.

“I am a Democrat, and I would like to be able to support this agreement,” Coons said. “But I have serious reservations about it.”

Schumer does as well. As an Israel hawk who will be the next Democratic leader after Sen. Harry Reid (D-Nev.) retires in January 2017, Schumer is seen as a bellwether among the handful of fence-sitting Democrats who may buck the White House and try to kill the sweeping accord. That leaves Schumer stuck between pro-Israel forces who have long been a key base of support and who are trying to kill the deal — and the White House and its progressive allies who are eager to secure a centerpiece of Obama’s foreign policy legacy and stave off a potential war.

Schumer will be criticized no matter what he does. If he tries to lobby members against the deal, he’ll be lashed by the left for undermining both President Barack Obama and Hillary Clinton and precipitating another conflict in the Middle East. If he quietly opposes the deal, he’ll be criticized by his hawkish Israel supporters for not doing enough to scuttle the agreement.

And if he supports it, he’s bound to get slammed by powerful Jewish donors and constituents who have long been among his staunchest supporters.

“Boy, I’m glad I’m not Chuck Schumer, I’ll tell ya,” said a smirking John McCain (R-Ariz.), a friend of the New York Democrat. “He’s got the toughest vote of his career coming.”

Congress has 60 days to consider the Iran nuclear agreement, which was reached between the United States, five world powers and Iran, meaning decisive votes will occur no later than September 17th. The agreement seeks to pare back Iran’s nuclear program, opening its facilities to inspections and monitoring, in exchange for lifting sanctions.

Lawmakers will vote on the deal that would lift legislative sanctions, which have been key to bringing Iran to the negotiating table and would provide major economic relief to the country if Congress lets the deal go through. Republicans will need a veto-proof, two-thirds majority to scuttle the deal, a high bar that will require a sizable bloc of Democratic opposition.

Skeptics in both parties fear the plan will make Iran richer but do little to curtail the country’s nuclear ambitions. Nowhere is that feeling more prevalent than in New York, with one of the most politically active Jewish populations. Last week, Rep. Grace Meng (D-N.Y.) announced her opposition to the deal, and one New York Jewish Democrat, Eliot Engel, expressed deep skepticism of the agreement.

“There are a number of parts of the deal that trouble me,” Engel said in an interview. “The main problem I have is that this deal will give a lot of money to Iran. Iran will be awash in cash, and they will be able to use it to fund their terrorist activities.”

The New York and New Jersey delegations have been the top focus of groups trying to kill the agreement, and there’s evidence they are making headway. In New Jersey, Sen. Robert Menendez sounds like a “no” vote, while Sen. Cory Booker is undecided. In New York City, the group Citizens for a Nuclear Free Iran spent $1.6 million on broadcast television and $119,500 on cable between July 16-July 30 advertising on the issue, according to a media tracking source. Secure America Now, a hawkish group trying to kill the deal, has organized the call-in campaign to Schumer.

“You will always get phone calls when you’re from New York,” Schumer said. “Hundreds of them on every issue.”

Indeed, Schumer is feeling heat to support the deal, too. The National Iranian American Council bought a full-page New York Times ad in support of the deal in July and is delivering petitions to his local offices and hoping to blunt efforts of opponents at town halls this month. J Street, a liberal Jewish group, is also pressing Schumer to back the nuclear pact.

Schumer will “have the support of the majority of American Jews” if he backs the deal, said Jessica Rosenblum, a spokeswoman for J Street.

Schumer has long sought to avoid alienating large segments of his caucus by taking vocal positions on divisive issues; when he has to take a stand, he typically keeps it low-key. Many expect him to wait to announce his opposition, possibly until the end of the process, and to do little to advocate internally for others to join him.

If Schumer wanted to persuade members to side with him, “Chuck would have let his intentions known a long time ago, and everybody would have known,” said Sen. Joe Manchin (D-W.Va.). Winning over members now, Manchin added, “would be much more difficult.”

The Iran vote could reverberate for Democratic senators facing tough reelection races in the coming years, especially if they back the accord and it fails to rein in Iran. Only one of them, Colorado’s Michael Bennet, is up in 2016; several others will be on the ballot in 2018.

Sen. Claire McCaskill (D-Mo.), a moderate who faces voters in three years, said she’s still carefully weighing the agreement.

“Schumer is not going to move anybody on this,” she said.

“I think he’s conflicted,” McCaskill added. “Many of us are. It’s hard.”

Sen. Jon Tester (D-Mont.), another moderate up for reelection in 2018, said Schumer would have “none, zero, nada” sway over his vote.

“Don’t tell Chuck that,” Tester joked.

So far, just one member of the Senate Democratic leadership team has voiced his position on the matter — Minority Whip Dick Durbin (D-Ill.), who supports the plan. That’s far different than the House, where Minority Leader Nancy Pelosi (D-Calif.) announced her backing almost immediately after the deal was announced. In the Senate, the other members of the leadership team, including Reid, Schumer and Sen. Patty Murray (D-Wash.), are playing coy.

Asked why he hadn’t made a decision yet, Reid replied: “Have you made a decision?” Informed that reporters don’t cast votes on bills, he responded, “Yeah, well” and then walked into the Senate chamber.

Steven Shepard contributed to this report.