Mitt Romney and Rick Santorum are creeping up on President Obama as new polls show the president’s approval rating at its lowest level ever. Obama now leads Romney 47 percent to 44 percent, down from a 6-point lead over Romney in February. The president holds a similar advantage over Santorum, polling at 48 percent to 44 percent. The CBS News/New York Times poll indicated that the Republican surge is at least partially attributable to Obama’s declining approval rating, which has fallen to 41 percent, down 9 points from a month ago. Romney ruled out picking Santorum as his running mate on Monday, saying the former Pennsylvania senator was not conservative enough. A Gallup poll showed, however, that the president’s approval rating was at a nine-month high.