July 19, 2012 (Written by Tony Man – Sun Sentinel) WEST PALM BEACH— President Barack Obama, whose hopes of winning re-election may hinge on Florida, flew into South Florida on Thursday evening to court two key constituencies: seniors and Jews, groups that may determine if he gets a second term in the White House.At the retiree-rich Century Village condominium community west of West Palm Beach, Obama took aim at Republican challenger Mitt Romney with one of the most potent weapons in the Democratic arsenal: protection of Medicare. Romney, the president warned, “plans to turn Medicare into a voucher program.”