HARTFORD, Conn. (CBSNewYork/AP)Former U.S. Sen. Joe Lieberman said he believes the effort to kill the Iran nuclear deal on Capitol Hill is gaining momentum.

Appearing Wednesday at a panel discussion in Manhattan on the Iran deal, the former Connecticut senator said he believes at least two-thirds of his former colleagues — enough to override a presidential veto — either oppose the agreement or are reading through the more than 150-page deal with a growing sense of alarm.

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Polls show voter consensus is shifting to the negative, and that’s taking the Obama administration by surprise, Lieberman said.

“Apart from all the details, here’s what I think is turning the American public against the deal: They don’t trust Iran,” the 2000 vice presidential candidate told WCBS 880’s Paul Murnane. “I mean, how can you make a deal with a country that says they want to kill us?”

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Lieberman said ultimately the agreement would open the door to a nuclear Iran and there’s nothing in the deal about the nation’s rhetroic and behavior.

The Republican-led Congress is in the midst of a 60-day review of the deal, and is expected to vote in September on a resolution of disapproval that Obama has vowed to veto. The administration’s goal is to ensure it has enough Democratic votes to sustain the veto.

Obama has aggressively courted Democrats, holding sessions at the White House. He’s also sent his Cabinet members to Capitol Hill for briefings and hearings.

Both sides are urging members to decide and announce their positions, in the hopes that those who have gone public will inspire others to follow.

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