I have heard alot of answers to that question, but the most common answers are: 1–Bravery on a personal level, 2–Independent, 3–Opposes Washington on some issues.

The only one that can be vaguely claimed is #1–he may have been independent or a maverick and he has opposed some of the Repub issues in the past–but his recent flipping on positions has shown that he is a team player.  What issues?  Bush tax cuts he opposed them before he supported them, just to mention one such flip.

Then there is #1..yes he was a POW and yes he showed bravery under those conditions.  He originally opposed the use of torture but once he was the presumed Repub nominee he supports torture.  I find that a bit much, as a POW he was subjected to torture and was opposed to it, before he supported it for political gain.

Nomne of this makes him brave or an independent or a fighter, it does however make him an opportunist.