"Winning" the "War" in Iraq

According to Joe Klein, John McCain said the following yesterday in New Hampshire:

This is a clear choice that the American people have. I had the courage and the judgment to say I would rather lose a political campaign than lose a war. It seems to me that Obama would rather lose a war in order to win a political campaign.

Klein dismisses the comment as "unpresidential" and "sad."

I won't quibble with that, but I have some more basic questions. Would someone please define the words "win" and "war" for me in the context of the current situation in Iraq? Because it's just not clear to me what McCain means when he says those words.

If the American occupation of Iraq is still a war, then who are exactly are we fighting it against? And how will we know when we have won?

I could understand it if McCain would argue that we have to stay in Iraq until its government is capable of maintaining at least the level of security currently in place. But all this talk of winning and losing obscures that goal. Stabilizing Iraq isn't a war and it isn't a game--and it's too complex of a process to lend itself to such simplistic rhetoric about winning or losing.

Given Bush's scandalously low approval ratings, one would think McCain and his campaign staff would be more careful to avoid sounding as simplistic and binary as the current president is known for sounding. However, it seems to be increasingly an open question as to how in touch with the situation in Iraq McCain is anyway. Trying to dumb down your talking points to score cheap political points with unsophisticated voters is bad enough, but actually believing such statements is outright frightening.