Mitt Romney won this first debate, judging by style, by his ability to get the message out, and by substance. Whether he did well enough to swing the polls back to parity is questionable. The Republican echo-chamber is likely to cheer loudly and their enthusiasm will tick up. Democrats will mutter about why Obama didn't mention Romney's "47 percent" gaffe, and campaign outsiders will mumble about the campaign's alleged insularity and arrogance.

Maybe the bar was set too low for Romney. He proved himself, yet again, in case you didn't watch the GOP debates, to be a strong competitor in full command of his brief, and importantly, he was able to articulate a consistent message that differed from that of the president's.  

On almost every question, Romney found a way to fold in the premise that Obama's over-reliance on government had hurt the middle class, and that Obama has done nothing to give anyone any reason to believe his next four years will be any different.

Since Jim Lehrer decided to stay out of the way for the first hour, he did not provide the service Obama most required of the moderator, which was to serve as a fact check/reality board for both candidates. Instead of prodding Romney to, for example, explain the holes in his deficit plan, he left that task to Obama. A robot saying "Your response?" would have been just as effective. Lehrer found his voice with a half an hour to go, but he let Romney get away with a number of significant distortions and omissions.

This first debate shows why it's so tough to be an incumbent in an economy that, frankly, is anemic and barely growing. It didn't really matter that Romney didn't present a plan; it did matter that he presented a vision that cohered. A lot of people watching the debate will see Romney's energetic performance, remember his theme, look at a halting Obama, and say, OK, well, there ARE two people running.

This is another problem for incumbents who believe they are smarter and more wily than their opponents: They are bound to be on the defensive in direct policy debates. Romney (as James Fallows has noted) is the consummate happy warrior in debates. Much was made of Obama's mien — smirks, his head down, his unrefined responses; that stuff matters marginally for incumbents because voters already know that Obama is not the best policy debater in the land.  

Just as Democrats are right to be cautious about Obama's chance at running the table, Republicans should be cautious about believing that Romney was strong enough to fundamentally change the dynamics of the presidential race. Will women shift back to Romney, given the consistent hammering from Obama's television ads? Probably not. It's easy to get amped up about the effects of one debate. If Obama is consistently lackluster, what can be written off today as a rare lack of self-control from a man who is a master of it will turn into a story — a story of a president who is diffident and tired. 

Nothing begets enthusiasm in the final weeks of a race like enthusiasm. 

Why didn't Obama do better? Here's some speculation: He is not as good at these formats like Romney is. He was too cautious ... even about appearing too flip and arrogant, which might have itself come off as arrogant; he didn't clip his answers; he didn't remember to say what he intended to say; he spent the day dealing with Turkey and Syria; he let his disdain for Romney show. I think all of those contributed to some degree. But fundamentally, when it comes to domestic policy, Obama just doesn't have a very good affirmative argument to make. That's a consequence of being a crisis president of a country where, as some are now saying, the old dismal is the new normal. 

Here are some grades:

Overall: (impressionistic!)

Romney: B+ 

Obama: C 

Substance:  (who made the best points? Who told the truth?)

Romney: B

Obama B+

Style: (if you turned the sound off, how would the debate look? If you turned the radio on and the television off, how would it sound?)

Romney: A-

Obama: C

Presentation/Argument  (for those watching, what came across in terms of an argument or a message)

Romney: A

Obama: C