President Barack Obama's approval rating has plunged below 50 percent, and Republican front-runner Mitt Romney would beat him if the election took place today, a poll showed Monday. The survey, by ABC News and The Washington Post, indicated that only 46 percent of Americans now approve of the way Obama is handling his job, and 50 percent disapprove as he took a hit from rising gas prices. The situation was a reversal from early February, when 50 percent approved of the president's performance and 46 percent disapproved. The survey was released as the battleground for the Republican presidential nomination moved...