Who most benefited from the debate series?

[Landslide Lyndon]

Romney is the obvious answer. Frankly I'm mystified as to why the first debate moved his numbers on such a historic scale. It seems as if voters were looking for an excuse (any excuse) to embrace the challenger and when they found one after the first debate, they rushed to his camp.
 
That would be a logical thing to happen if Obama was an unpopular incumbent like Carter was in 1980. But with his approvals hovering around 50% and the fundamentals trending favorably (economic growth-albeit slow, booming stock market, falling unemployment, unpopular wars winding down) I would have expected a much more modest effect on his numbers.

If anybody can offer me a non-hack explanation ("OMG, RACISM!!!" or "Illegitimate Kenyan Socialist Obumbler was xposed to Amurica!!!") then he is more than welcome.