U.S. investigators are looking into whether embattled New Jersey Governor Chris Christie misused about $2 million in Superstorm Sandy relief funds for an ad campaign that put him in the spotlight in an election year, a lawmaker said on Monday. Already enmeshed in a scandal over snarled traffic at the George Washington Bridge, Christie, a rising star in the Republican party, is now being audited by the Inspector General at the U.S. Department of Housing and Urban Development, said New Jersey Congressman Frank Pallone Jr., a Democrat. The inspector is focusing on a federally financed $25 million Jersey Shore marketing...