President Obama vetoed a bill that would approve construction of the Keystone XL pipeline on Tuesday, marking only the third time he's killed congressional legislation—and the first time he's done so since 2010. Obama repeatedly vowed to veto the bill if the newly Republican Senate passed it. Majority leader Mitch McConnell said the Senate will vote on overriding the veto next week. Sixty-seven votes are needed to defeat Obama, which Republicans don't have.