Senator John McCain is battling an aggressive form of brain cancer that will likely kill him, and he knows this. This grave reality seems to have given him a new outlook on his role as a United States Senator. In fact, his lease on life is so new and refreshing that he is going up against his best Senate friend, Senator Lindsey Graham (R-SC). Now that McCain is firmly in the  no  camp, the GOP can only lose one more vote, as Senator Rand Paul (R-KY) is already a hard  no  vote as well.This bill is even more radical than the one McCain killed before, with a drastic move on the Senate Floor as Senate Majority leader Mitch McConnell looked on with his stony turtle face signaling humiliation and rage. On this bill, McCain says: I cannot in good conscience vote for the Graham-Cassidy proposal. Here is the full statement, via Twitter:BREAKING: Sen John McCain comes out in opposition to Graham-Cassidy: " I cannot in good conscience vote for the Graham-Cassidy proposal" pic.twitter.com/Xy50UPAZUo  Evan Rosenfeld (@Evan_Rosenfeld) September 22, 2017His original statement in an interview was less promising, but he voiced grave concerns already, so this is really no surprise. He truly is an American hero. Here is the original interview:WATCH: Senator John McCain says he s comfortable with the Graham-Cassidy bill as long as the Arizona governor signs off on it. pic.twitter.com/f3oR1JUsKr  NBC News (@NBCNews) September 19, 2017