McCain self destructed in the campaign for the 2000 presidential run.
In fact after he was DOA, at the Republican Convention, he (on nation wide TV) did the following ...
"A display of John McCain’s anger, live on MSNBC. As he walked through a crowd on his way to delivering his concession speech Tuesday night, NBC’s Maria Shriver asked him "how do you feel?" McCain spun around and sternly commanded Shriver: "Please get out of here." The rebuke stunned MSNBC anchor Brian Williams."
From here
McCain may be a force, but he is uncontrollable under pressure and can be programmed to implode. The Karl Rove replacement should be able to deal with him.
JMHO
