The conventional wisdom, at least in the traditional media, seems to be that Sarah Palin "won" because she didn't hurt McCain in her debate. Because she didn't implode by falling flat on her face and because she sounded slightly more intelligible than she did with Katie Couric, the debate was a net plus for the McCain camp. This logic ignores the fact that McCain is behind in the polls and lost another opportunity to make up ground, a "tie" is a victory for Obama who just needs to hold serve for the next 30 days. But it also completely ignores how Palin was damaging to McCain throughout the course of her debate, and how she completely undermined the meme that McCain was desperately trying to sell throughout the course of his.
The core of McCain's argument from the first presidential debate was that Obama doesn't understand. That was the mantra that he repeated over and over. McCain tried to paint Obama as someone who perhaps means well, but just doesn't have the years in Washington to truly grasp such complex issues as how to stimulate the economy and the best way to bring stability to the middle east. McCain couldn't even explain why Obama's logic on various issues was flawed he could only argue (in essence) that although what Obama says sounds good, Obama (and you) hasn't been around long enough to understand why he's wrong. The implication being that if Obama were to spend a few more decades in Washington, he would come around to McCain's position. This is the exact opposite of the meme Palin was pushing during her debate. Now obviously Palin couldn't attack Obama on naivety, especially not with Biden standing right there. But in defending herself and touting her positives, Palin argued that not only aren't years in Washington essential to being able to make good governing decisions, years in Washington may actually be detrimental. This is an argument she'll fall back on, whenever she's stumped on a question of policy or foreign relations. She'll say, "I may not have fancy Washington knowledge, but I don't need it because I'm from a small town." She goes beyond arguing that experience isn't important to arguing that knowledge, at least knowledge gained in Washington, isn't important. Not exactly the message that McCain was trying to sell.
Biden by contrast had superb message discipline with Obama. What Biden did during his debate was exactly what Obama did during his; he constantly linked McCain to Bush. Other than the handful of personal anecdotes, Obama could have delivered Biden's debate performance. In contrast, Palin could not have duplicated McCain performance and tried to paint Obama as naive, and McCain could not have given Palin's performance and decried being from Washington.
Further undermining McCain's message was the fact that Biden has 30 years of experience in Washington. After the first debate, some may have wondered if McCain had a point, maybe Obama is too green. But after the second debate, after watching Biden, who 91% of CBS's poll respondents thought could be an effective president if neccessary and who a whopping 98% felt was knowledgeable on the issues, support all of Obama's positions, the naivety argument is out the window. Joe Biden is a lot of things, but naive isn't one. Additionally, Biden never once made an attack which could also be applied against Obama. He never once questioned Palin's experience or suggested that she may not be ready for the job. He kept his attacks focused squarely on policy.
It will be interesting to see what tactics McCain takes in tomorrow's debate. People aren't buying his naive argument, and Sarah Palin isn't helping to push that meme. By all accounts McCain will attack more, but the problem he faces is that if tomorrow's argument against Obama is his questionable associations, that will be the third major theme in three debates. It will seem a little desperate (which it is), like he's flailing around (which he is). If Ayers was such a big deal, why didn't you bring him up earlier? Meanwhile Obama will stay consistent. His message tomorrow will be that McCain just doesn't get it, and that McCain's policies are a continuation of the Bush years. People are desperate for change, and McCain has yet to effectively argue that that's what he'll deliver.