In a major victory for President Barack Obama, Democratic Sen. Barbara Mikulski of Maryland announced support for the Iran nuclear deal Wednesday, providing the White House the votes it needs to prevent Republicans from scuttling the agreement. The announcement means that at least 34 senators -- the number required by the Constitution to sustain a veto -- will back Obama in vetoing a Republican resolution to disapprove of the deal. While majorities of both the GOP-controlled House and Senate are expected to vote against the agreement, supporters of the multinational accord that aims to curb Iran's nuclear weapons program are...