Senator Edward Kennedy is at Duke University Medical Center today for a surgery to remove a malignant glioma-the brain tumor that caused his May 17 seizure. He might remain awake for the surgery, so doctors can remove as much of the tumor as possible while checking to make sure that critical functions like movement or speech remain intact. Needless to say, it's a risky procedure, and our fingers are crossed for Kennedy and his family. Responding to news of the tumor McCain said Kennedy "remains the single most effective member of the Senate."UPDATE: Doctors reported that the surgery was a success.