MANCHESTER, New Hampshire – Days after her former fellow New York senator Chuck Schumer came out against the White House-backed deal with Iran, Hillary Clinton on Monday warned supporters at a campaign stop here that “all bets are off” if the agreement fails.

“I’m hoping that the agreement is finally approved and I’m telling you if it’s not, all bets are off,” Clinton told about 500 supporters at the base of the McIntyre Ski Area. “That’s a very bad signal to send in a quickly moving and oftentimes dangerous world.”

The White House has been struggling to secure enough votes to sustain an all-but-assured veto of an expected Senate vote to reject the deal, which would curb Iran’s nuclear program. Critics say the deal will allow Tehran to attain nuclear weapons and given them access to funds they could use to fund terrorism.

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The White House effort was dealt a blow late Thursday night with the defection of New York Sen. Chuck Schumer, a top Democrat in the Senate who is in line to become the party’s leader when Harry Reid retires.

“I have decided I must oppose the agreement and will vote yes on a motion of disapproval,” Schumer wrote in a blog post announcing his decision. The White House condemned Schumer decision Friday unusually harshly.

Close video Schumer’s opposition raises nuke deal stakes Former Amb. Joseph Wilson, who served on the National Security Council under President Clinton, offers his expertise to Alex Witt on how the Iranian government will interpret U.S. congressional deliberations on the nuclear deal. Former Amb. Joseph Wilson, who served on the National Security Council under President Clinton, offers his expertise to Alex Witt on how the Iranian government will interpret U.S. congressional deliberations on the nuclear deal. share tweet email Embed

But in a lengthy and full-throated defense of the Iran agreement, Clinton recounted her work as secretary of state to build an international coalition to implement sanctions on Iran.

Without mentioning Schumer, Clinton called on supporters here to speak out in favor of the deal. “You’re going to hear a lot about it in the weeks ahead, so please educate yourself. Speak out about it. We have to pursue diplomacy if we expect to be able to solve difficult problems with the rest of the world supporting us,” she said.

As president, Clinton said she would rally other countries to keep Iran in check: “I know how to build a coalition against them because I did it once.”

Clinton and Schumer are political allies and friends. Both represented New York in the Senate at the same time.