The first debate between President Obama and former Massachusetts governor Mitt Romney is in the books.

We live-tweeted the proceedings but also jotted down a few deeper (more than 140 characters) thoughts on what we saw.  Our first thoughts are below; we reserve the right to revise and extend our thoughts as we marinate on the first debate.

Agree or disagree?  Have a takeaway of your own? Offer it in the comments section below.

* The grimness of Barack Obama: There's a fine line between sober/serious and grim/uninterested when it comes to the optics of these debates, and the incumbent was on the wrong side of it Wednesday night. Whether it was his habit of looking down for the majority of Romney's answers or the pique he displayed when debate moderator Jim Lehrer interrupted him, Obama looked like he'd prefer to be somewhere else.  In many ways what Obama seemed to be doing was taking on the persona he used to much success in 2008 when he was careful to show he was ready for the job. But, now that he has been in the job for four years, Obama's demeanor came across far less well.  Remember that voters see their vote for president as electing a leader not just a set of policy positions. And, Obama the glum is not the leader people want to vote for.

* Romney's prepared competence...and more: If the main goal for Romney in this debate was to show he could stand on stage with the president and handle a wide-ranging discussion on economic policy, he did so with flying colors. Romney's strength as a debater -- as demonstrated during the GOP primaries -- is his ability to recall massive amounts of information with little seeming effort and he did that time and again on Wednesday night. Romney didn't just deliver a sort of hyper-competence, however. He was at times funny -- his quip at the beginning of the debate about the president spending his wedding anniversary at a debate was a good one -- and delivered plenty of quotable moments ("you pick the losers", "you're entitled to your own airplane and your own house") that will be replayed again and again in the after-action analysis.

* Numbers, numbers and more numbers: For the first half of the 90 minute debate, it appeared as though Obama and Romney were trying to one-up one another with how deeply they could go into the numbers behind certain policies.  The goal for each man was clear; Obama wanted to show that Romney's math doesn't add up, Romney wanted to hold the incumbent accountable for the spending decisions he has made in the first four years. But, our strong sense is that for undecided voters watching the debate most of that segment passed in a blur of numbers, giving them no broader sense of what the candidates want to do -- and why.  Moderator Jim Lehrer seemed content to let the two men go down the numbers wormhole, perhaps believing that such a conversation was what the public wants from the two men. And maybe it is. But we would be surprised.

* No Bain, no "47 percent": Inarguably, Obama came into tonight's debate with more obvious set-piece attacks on Romney.  But, he seemed to be disinterested in using them. He made no mention of either Romney's "47 percent" comment or Romney's work with Bain Capital -- two demonstrably difficult topics for the former Massachusetts governor.  Our guess is that Obama and his team made the calculated decision not to hit Romney on either matter because a) it wouldn't look presidential and b) it's already penetrated deep into the political consciousness of the electorate.  Maybe so. But does it ever hurt to repeat the attacks that have been proven to work against your opponent?

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