Portman rules out 2016 bid for White House

WASHINGTON (Reuters) - Republican Senator Rob Portman, a former White House budget chief and trade representative who broke with fellow conservatives to back gay marriage, has ruled out a presidential run in 2016 and will seek a second term. In a statement on Tuesday, the Ohio lawmaker said he could not be an effective senator and campaign for the White House at the same time, and sees potential in the new Republican majority in Congress to tackle issues such as revamping the tax code, overhauli