his position for a "surge" in afghanistan was a cynical campaign tactic. he couldn't be against the iraq war and the afghanistan war (and yes, I realize that they are actually battlefields of the same larger GWOT), so he oppounistically came out in favor of a surge in afghanistan so he didn't look like a pacifist, and now he's stuck with it.
I don't think a surge will work in afghanistan. it strikes me that was the lesson that the soviets learned in the 80s. not that the US millitary wouldn't do it differently, but given the terrain, the culture, and the abject lack of any central authority in the history of that forsaken country, I don't see how a surge could work. not to mention that fact that it's a pile of rocks.