This quote is really just covered in irony. John Kerry, who will forever be known as a serial flip-flopper, brings up the fact that McCain has repeatedly changed positions on a number of issues, and the response from Schieffer is that bringing up such issues is an attack on his integrity. Wow.
Bob Schieffer, on Face the Nation, responding to John Kerry stating that McCain has completely changed his position on a large number of issues:
“Are you attacking John McCain’s integrity?”
The way the guardians of the discourse see it, just noting that McCain has changed his mind is beyond the pale and I can't, for the life of me, figure out why that is. I don't know of another figure in American politics who is consistently painted in such a favorable light by the media and is afforded as much room for error.
The only other person that even comes close is Colin Powell, so it may be a military thing. Yet, if it was, people like John Kerry, Wes Clark, Bob Kerrey, Chuck Hagel or Max Cleland would also be afforded the same privileges by the media- but they aren't. It could be that McCain's history as a POW has set him apart from others, so that he is viewed as having integrity than any of the others. But should his experience be valued more than triple-amputee Cleland or Medal of Honor winner Kerrey?
Could it be his support for Campaign Finance Reform? Probably not. If it was, a bevy of liberals would get the same favorable treatment from the press.
At the end of the day, I think the simple reason for this deference to McCain is part of a vicious circular logic. The press loves McCain because he is a maverick. Why is he a maverick? Because the press says that he is.