The media regularily puts McCain and Palin forward as Mavericks.

I see it in Palin.

But, is it true for the much older, career politician McCain?

Why so?

Below are some definations of the word:
http://www.wordreference.com/definition/maverick

http://www.thefreedictionary.com/maverick
http://www.developing-leadership.com/definition-of-a-maverick.html