Three more Democrats in the U.S. Senate announced their support for the nuclear deal between Iran and world powers on August 18, raising to 23 the number who back the deal and increasing the likelihood that President Barack Obama can veto Republican attempts to block the accord.
Obama needs at least 34 votes to sustain a veto in the Republican-dominated Senate.
In the Republican-dominated House of Representatives, where 48 Democrats have expressed support for the deal, Obama needs a total of 146 votes to sustain a veto.
Both chambers of the U.S. legislature are expected to reject the deal in September amid near universal condemnation of the accord by Republicans.
But Senate Majority Leader Mitch McConnell acknowledged on August 17 that Obama has "a great likelihood of success" in gathering enough support to sustaining a veto against the attempts to block the accord.