It's a nationwide issue and it affects McCain's state, but with the flap over earmarks, he can't just seek to relieve Arizona's issue. To my understanding, cosponsoring a bill or amendment is about as simple as going on record to cosponsor. This is an amendment and has a lot of other stuff that Alexander and Corker may not be comfortable with. At least it is a step, and I bet the TVA is aware of it.
"Here fishy fishy."