If this guy votes against it, it's over, because a big coalition will vote whichever way he does. And all signs are that he will. That is, if he's interested in being re elected.
Iran nuclear deal Growing signs Schumer will oppose it - POLITICO
Lets educate you, It was not "Obama's Iran Deal". Obama also will veto it, and the other P's plus Germany and the IAEA are not backing down. Obama has the pen.
Obama and Kerry (the Batman and Robin of world diplomacy) have been the public face of this deal and Obama has no qualms about evoking his "Obama Doctrine" (big eye roll) in insuring the US would guarantee Israel's security should Iran threaten.
Not China. Not Russia. Not Germany, the UK or France. But the U.S., according to Barry Obama (who will be long out of office, by the way).
He should get his veto pen ready. This deal doesn't look too certain to pass.