President Obama might have saved his campaign at Tuesday night’s presidential debate. Not that his performance was all that great.

At the first presidential debate two weeks ago, Obama seemed prickly and disengaged. This time around, he retired the arrogant grin and delivered his lines with force. He did voters the courtesy of bringing his A game, instead of conceited complacency. Mitt Romney, meanwhile, went from confident and affable two weeks ago to defensive and pushy Tuesday night. He often sounded flustered, even repeatedly arguing petty points of procedure with moderator Candy Crowley. By the end of the debate, members of the audience clapped after Crowley called Romney on a fact he got wrong.

Obama also did a better job hitting Romney on a few matters of substance. The president calmly added up the numbers in Romney’s mathematically-challenged tax plan, insisting that Romney the investor would never accept such a “sketchy” deal. Romney’s response to the criticism of his numbers was about as convincing as his usually are: “Of course they add up,” he insisted, following that with no plausible reason to believe him.

On substance, however, Obama still only looked great relative to Romney’s unrealistic tax plan.

President Obama clearly came ready to play Tuesday night, and Mitt Romney may have touched the borders of disrespect, but in the end I came away convinced (once more) that this race will go down to the wire.

On the economy, Obama made a good case that the glass is half-full. Romney made a good case that the glass is half-empty. Obama thinks he’ll win by contrasting his and Romney’s values, not by offering any compelling agenda for a second term. Romney thinks he’ll win on Obama’s economic record, and on being a credible-enough alternative to make things better.

The country seems pretty perfectly split on this, so it may well come down to who can get their voters out in what numbers in key states. Get ready to stay up late on Nov. 6. Or even for the days after.

Separately, the second debate was yet another reminder that, on many of the issues that matter, we’re in a state of bipartisan denial or evasion. Three quick examples:

Four years ago this fall, Democrats were unnerved because then-Sen. Barack Obama didn’t seem to want to fight for the job of president. He appeared willing to let the Republican ticket run all over him. An unsettling sense of deja vu had engulfed Democrats ever since President Obama lost the first debate with a horrendous performance that left friend and foe alike asking what MSNBC’s Chris Matthews asked pointedly, “Where was Obama tonight?”

No one’s asking that question now. Mitt Romney did okay. But Obama won.

The same aggressive Romney who cleaned Obama’s clock in Denver showed up on Long Island. (His hectoring of the debate moderators is growing tiresome, but I digress.) The somnambulant president of two weeks ago gave way to a wide-eyed and aggressive president tonight who refused to Romney’s attacks laying down and who was more than willing to proactively take the fight to his Republican opponent.

This was the night in which the conservative closed information feedback loop and its close cousin, lazy mendacity, caught up with Republican presidential nominee Mitt Romney — in a big way.

The topic was Libya. It’s an issue that should work well for the challenger; surely at the very least, Barack Obama’s administration had a tragedy on its hands, one that might have been preventable, and one that most seem to think Obama and his administration have handled poorly after the fact. There would seem to be a variety of attacks available. Was Obama’s Libya intervention a mistake? Was there something about the Libya attacks that undermined Obama’s claim of policy competency? Obama’s handling of the Arab Spring? Romney had to think himself lucky when the only foreign policy question of the night was on this topic, teed up perfectly for him.

“Who won the debate?” is not the question of the night, since your answer to that probably depends upon your party registration.

Instead, the question to think about is, Which candidate do you end up trusting the most?

President Obama regained his footing Tuesday night and demonstrated in the second presidential debate that he was up to the challenge. He knew his lines and didn t hesitate to mix things up with Mitt Romney. He showed he was willing to fight for his positions.

Most important of all, he came across as genuine.