WASHINGTON (AP) — A procedural snarl and a single senator's objections could force another partial shutdown of the Federal Aviation Administration.Senate Majority Leader Harry Reid said Wednesday that Senate rules don't allow lawmakers to drop their current consideration of a disaster aid bill and shift to a stopgap funding measure for FAA and highway programs without the consent of all lawmakers.But an Oklahoma Republican, Sen. Tom Coburn, is refusing to give his consent. Coburn wants to change the stopgap bill that passed by the House on Tuesday by eliminating highway program spending on bike paths, beautification projects and other so-called transportation enhancements.Republicans say the Senate could have passed the transportation bill in time if Reid hadn't brought up the disaster bill first.An FAA shutdown could occur at midnight Friday.