Bill Nelson backs Iran deal
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Sen. Bill NelsonClarence (Bill) William NelsonEquilibrium/Sustainability — Presented by The American Petroleum Institute — Climate change turning US into coffee country Elon Musk mocks Biden for ignoring his company's historic space flight How will Biden's Afghanistan debacle impact NASA's Artemis return to the moon? MORE (D-Fla.) on Tuesday threw his support behind President Obama's nuclear agreement with Iran, joining a string of Senate Democrats backing the deal ahead of a five-week recess. 

"I acknowledge that this had been one of the most important preparations and will be one of the most important votes that I will cast in the Senate," he said. "Unless there is an unexpected change in the conditions and facts before the vote is called in September — and it will be called on the very first day that we return in September — unless there is an unexpected change, I will support the nuclear agreement."
Nelson added that there is "no other available alternative" that keeps Iran from getting a nuclear weapon for at least the next 10 to 15 years. 
He's the third Senate Democrat to come out in support of the agreement Tuesday, with Sens. Tim Kaine (D-Va.) and Barbara Boxer (D-Calif.) announcing earlier Tuesday that they will also support the agreement. 
Nelson, like Kaine and Boxer, called the deal the best option available to Congress. 
The Florida senator was one of roughly a dozen senators expected to face pressure from opponents of the agreement to buck President Obama and vote to kill the deal.
Republicans will need at least 13 Senate Democrats to join them in opposing the deal if they are going to able to override a potential veto from Obama. Groups seeking to kill the deal are expected to spend millions ahead of the September vote to sway undecided senators.
The GOP is largely opposed to the deal for a variety of reasons, including the lifting of an arms embargo, "side" deals between Iran and an international agency, and the fact that Iran doesn't have to release Americans as part of the deal. 
But Nelson warned that if Congress rejected the agreement, it could help quicken Iran's ability to get a nuclear weapon, adding that "without this deal, Iran's breakout time could quickly, quickly shrink from months to a handful of weeks or days." 
Last month, the United Nations Security Council endorsed the deal, paving the way for international and non-congressional sanctions to be waved even if Congress rejects the agreement. He added that if his colleagues reject the deal, those sanctions against Iran likely won't be reinstated. 
"[It's] a fact that we are having to face," he said. "Under a deal, we keep most of the world with us."