The media have been saying things like, "as long as she doesn't seem like a total idiot, she'll win." But I don't think that's right. I actually believe that substance matters in these forums a little more than that. One of the reasons Barack Obama beat John McCain in their first debate is that many viewers found him more substantive than they'd figured him to be. Whether they can remember specific things he said isn't the point. It's that he came across as knowledgeable.
So put it this way if you like: command of substance is a form of performance. A candidate could not get up there and, however charismatically and empathically, read from the St. Louis telephone directory. You have to know something.
The bulk of the voters that have come to disapprove of Palin over the past few weeks have been women. Disproportionately so. Women who, quite probably, feel insulted by the Palin pick. Women who sense that she's not ready and that she's the quintissential airhead hottie that represents one of the two major sexist memes against women--the other being the castrating bitch, something that the GOP has invested much time in painting Clinton as the exemplar. Giving a muddled, evasive performance tonight--which has got to be the best that she can offer--isn't really going to dissuade these women. They probably think (as do I) that Palin is going to set back their ability to be taken seriously, as she is a living embodiment of one of the prevalent sexist memes. The woman knows nothing. What's amazing is that that makes the GOP only love her more. That bespeaks volumes as to how debased that party has become.
I tend to think Tomasky is right here, for the simple reason that pundits don't set expectations: the American people do. And while a few Palin likers might come back to her if she has a not-so-bad performance, I simply don't think it will be enough to reverse the tidal waves of the campaign. In the end, I'm not much up on the media these days, because it seems to be an institution of rich elites whose primary goal these days is to try to get into the heads of ordinary folks to predict horserace nonsense. God forbid they actually try to educate the public on issues!