Eleven years ago Bob Bennett, then a Republican senator from Utah, made a fiscal sales pitch for including prescription drugs in Medicare coverage for seniors. "Medicare says if you go to the hospital and run up a bill of however many tens of thousands of dollars to stay that many days, we will pay for it," he said in June 2003. "But if you take the pill that makes the hospital visit unnecessary, we will not. That clearly doesn't make sense." Researchers at the University of Illinois and the Johns Hopkins University have made the broadest test yet of Medicare Part D prescription drug program's promise — that covering drugs would keep seniors out of the hospital.