As President Obama defies bad job numbers this week to widen his lead over the Republican ticket by as much as 4 points, he prepared to cite a new Medicare study Sunday that slams Mitt Romney’s health-care plan for seniors. According to the study, elderly Americans in 2023 would have to hand over as much as $60,000 more over their retirement for health-care coverage under Romney’s plan for Medicare. It is anticipated that Obama will cite the study, which was conducted by a Harvard academic and veteran of the Clinton and Obama White Houses, as he campaigns for a second day in Florida.