I haven’t even left for St. Louis yet and I already feel like I’m in the spin room at Washington University. To hear the spinners’ spin, there is no chance that either Sen. Joe Biden of Delaware or Gov. Sarah Palin of Alaska will utter a coherent sentence in the vice-presidential debate Thursday night.

The expectations aren’t just low; they’re in the Death Valley range. I’m not sure I remember such a vigorous race to the bottom, even when the world was coming to know a legally blond fellow named Quayle.

As Democrats in or near the Obama-Biden camp tell it, the concern is that the loquacious senator will talk too much, will be overbearing and condescending, too up-to-here with Beltway blather.

In the process, they say, he will make Palin’s lack of knowledge look not only acceptable but also somehow preferable to the know-it-all at the next podium.

“I just am afraid that Joe is not going to be able to shut up,” said one top Democratic fundraiser, who is close to the senator but who does not want to talk in public. “He keeps telling the debate prep people that he gets it, but I’m not sure he can control himself. He’s certainly never been able to in the past, has he?”

The downdraft on Biden is nothing compared with the hurricane of badmouthing from Republicans aimed at Palin. Some of it is strategic; some not. Some of it is comical; some of it has an air of desperation.

Much of it seems designed to explain in advance why Palin can’t do well—even though she got relatively good marks for her debate performance in the gubernatorial race in Alaska two years ago.

Here are some of the preemptively deflationary spin lines:

• Poor Sarah is/was over-prepared. This is the Karl Rove theory—that Steve Schmidt and the other debate briefers, who carted Palin off to Sedona for three days of prep work, filled her head with too many canned responses and a catalogue of facts. In the process, they stifled the “real” Palin—the Palin who lit up the night at the Republican convention in St. Paul last month. Of course that appearance was a carefully scripted speech. So it’s unclear whether that was the “real” Palin, or whether the “real” Palin will reveal herself Thursday night.

• She is the tribune of “Joe Sixpack America.” As such, Palin’s leadership qualities cannot fairly or appropriately be measured in a debate like this one. Palin herself has made this argument. Not only is it unfair to expect her to have Biden’s level of detailed knowledge; it’s the wrong way to judge her, since her most worthy quality is that she is “one of us.”
  
• The Media are biased: Look at the debate moderator. This is the latest pre-spin, though John McCain’s campaign itself is loath to get anywhere near the specifics. Debate moderate Gwen Ifill of PBS has a book coming out on Inauguration Day about the new generation of African-American political leaders. It’s called “The Breakthrough,” and one of the figures she focuses on is Obama. Conservative commentators such as Rush Limbaugh and Sean Hannity argue that the book presents a hopeless conflict, in that Ifill (whether she wants to admit it or not) favors Obama because a victory by him in November will boost her books sales. They may have a point, at least about appearances. But Ifill is highly respected, fiercely independent—and in the tank for no one. I asked a top McCain advisor what he planned to do about the situation and he had a one-word answer: “nothing.” But let’s see how the debate goes—and see if he sticks to his word not to bring it up. If the debate goes badly for Palin, my bet is that we’ll hear this one in the spin room Thursday night.
  
• She should have quit the race by now. This isn’t an intentional lowering of expectations by the McCain camp and its allies; rather, it’s a cluster of conservatives, led by George Will, who were mortified by her apparent lack of knowledge. Those feelings were only solidified by the governor’s devastating interviews with Katie Couric. At this point, it’s conventional wisdom that Palin isn’t ready for prime time. So it will be a form of victory if she merely makes it onto the stage in St. Louis.