Today, Sen. Barbara Mikulski of Maryland said she will back President Obama and vote to uphold the Joint Comprehensive Plan of Action -- better known as the Iran Deal. She is the 34th Senate Democrat to come out in favor of the deal, making it extremely unlike that it can be stopped.
To stop the deal, both houses of Congress would have to reject it, requiring a 60-vote majority in the Senate and a majority vote in the House of Representatives. After that, the rejection would go to the President's desk, and President Obama would veto it. Then, it could go back to Congress for a vote to override the veto. That's where the problem comes in -- 67 votes in the 100-member Senate are required to override a veto, and Sen. Mikulski's decision means that although some, such as Sen. Chuck Schumer, have announced their opposition to the deal, there are still already 34 Democrats supporting the deal -- and thus opposed to a rejection of it. That would block opponents of the Iran Deal from gathering the 67 votes necessary to override the veto.