This statement has nothing to do with bridge. Yet, it's from one of my very many smart bridge friends. Personally, I think that he nailed exactly what happened Wednesday night.
The reason Romney won the debate is because Obama has spent the last year arguing with a Romney of his own construction. He has built a whole litany of arguments to counter views that he claims Romney holds and policies he claims Romney proposes. So when he found himself arguing against the views Romney actually holds and the policies he actually proposes, he was completely unprepared.
Obama has similarly been misrepresenting himself and his own accomplishments. So, when forced to face the catastrophic results of the policies he has been pursuing the last four years, he has no answer.
His entire campaign has been based on denying the truth. That works fine for campaign ads, but it doesn't work well in a debate.