1. They're better with their backs against the wall
Heading into the first debate, it looked like Barack Obama was easily on his way to a second term. Then the President went into cruise control a little too early. Listless and unfocused, he was easily bested by a well-prepared Mitt Romney, who was eager to prove his political obituaries were being written too soon.
The President's performance widely panned, his campaign now in trouble, it was a much different Mr. Obama who showed up for the next two debates. His body language was better; his attacks were sharper; he was quick on his feet and even intermittently funny.
With the momentum, meanwhile, Mr. Romney may have backed off too much. In the final round, playing for a draw, he came off as almost deferential to the combative incumbent. For two highly competitive people, they both proved oddly capable of complacency when things are going their way.
2. They don't need teleprompters
Coming into the debates, there were questions about whether Mr. Obama could perform when he didn't have a text in front of him. And while Mr. Romney had more recent debate experience, those who had watched him at length cautioned that he could run into trouble when off script.
Both candidates validated those concerns at times: Mr. Obama with his rambling responses in the first debate, and Mr. Romney with the odd awkward moment (most memorably "binders of women" and his mishandling of questions about Libya).
But by the end of 4 1/2 hours of debate, both had also proved themselves more than capable of thinking on their feet, and pushing back when under pressure. Few viewers would have come away with the impression that the candidates lack an in-depth understanding of their policies or an ability to articulate them.
3. They don't have all the answers
The general view coming out of the debates is that there is lots of disagreement between the candidates on domestic affairs – including on medicare, other government spending and tax policy – and much less on foreign policy. This seems to be largely by design on Mr. Romney's part, since Mr. Obama is more vulnerable on his country's struggling economy than on its place in the world.
But on some challenges, the lack of daylight can also be chalked up to a mutual willingness to fall back on posturing in place of easy (or easy to articulate) solutions. That includes how to compete with China and other emerging economies, and how to handle the crisis in Syria and friction through much of the Middle East.
Considering those will be among the most consequential matters facing the next president, there's some cause for concern in the fact that we're little closer to knowing how he would deal with them than we were three weeks ago.