HARRISBURG, Pa. (AP) -- The leading sponsors of medical marijuana legislation say Gov. Tom Corbett didn't go far enough when he said he'd support the legalization of a marijuana extract to treat severe seizures in children. Sens. Daylin Leach and Mike Folmer wrote to Corbett on Friday to say they want to work with him on medical marijuana legislation that would help people, including adults, treat a wider range of illnesses. Corbett said Friday that he knows some people would like to see it broadly available, but his proposal is where he is willing to go. Even that may have trouble passing the state House. A spokesman for leaders of the House's Republican majority says they're concerned that federal law prohibits it and the U.S. Food and Drug Administration hasn't approved it.