There's a new Rasmussen poll that finds that more Americans think Jim Lehrer, Friday's debate moderator, will "try to help Barack Obama" than think he will try to help John McCain. (The vast majority either think Lehrer will try to play a neutral role or are unsure.) Since poll results that find the public suspects liberal bias on the part of the media tend to get more media attention than results that find the public suspects bias in favor of conservatives*, you can expect to hear a fair amount about the Rasmussen poll over the next few days.
So it's worth keeping in mind Jim Lehrer's performance in previous presidential debates. A few weeks ago, I described his bungling (and, intentionally or not, strongly pro-Bush) behavior during a key portion of the last debate between Al Gore and George W. Bush in 2000.
The short version is that Lehrer helped Bush falsely blur the differences between Bush and Gore on the Patients Bill of Rights by falsely suggesting the two candidates agreed on the issue. Then, when Gore asked Bush a straightforward question about whether Bush actually supported the same piece of legislation he supported, Lehrer told Bush: "Governor Bush, you may answer that if you'd like." So, in his role as moderator, Lehrer gave viewers the false impression that the candidates agreed (exactly the impression Bush wanted viewers to have) then, rather than pressing Bush to clarify his position, he made it optional. Naturally, Bush declined.
A longer version is available here.
There's another reason to think Lehrer's handling of the debate may (intentionally or not) end up helping McCain. In 1996, Slate's Jack Shafer described Lehrer's style:
Yet, even though he knows that most politicians, CEOs, and activists who appear on his show are accomplished liars, he offers little in the way of interruption or contradiction.
Lehrer himself has said he doesn't think it is his role to say someone is lying, even when he knows that is the case. If the general media consensus that John McCain has run the more dishonest campaign is correct, Lehrer's style is likely to benefit McCain.
* In May, a CBS/New York Times poll found that only 8 percent of Americans thought the media had been harder on McCain than on other candidates, while 28 percent thought the media had been easier on McCain than on other candidates. You probably didn't hear about that poll result; the media ignored it.