Anything can go wrong in a debate, and Obama is not a perfect debater.

Somebody must be up and somebody must be down. Trouble is, campaigns are messy, subtle creatures that don't follow convenient narratives.

Climate change was a point of division between Obama and Republican rival Mitt Romney. The president declared climate change a global threat, acknowledged that the actions of humanity were deepening the crisis, and pledged to do something about it if elected.

American exceptionalism is the recurring character in the nation's narrative.

For a man who has compared himself to Theodore Roosevelt and the nation's challenges to those of the Gilded Age, Obama put forward a tepid agenda.

This is Romney's biggest political weakness. His policy flip-flops and the general sense that he's not comfortable in his own skin leads voters, including many supporters, wondering about his core values.

It's a deft trick to turn American exceptionalism into an exceptional political tactic.