Palin may not defeat Joe Biden, but she doesn't have to. If she comes close and avoids a major gaffe - a "Tina Fey Moment" - she will improve her standing with the Republican base and may help John McCain's effort to win critically important swing voters.

Several factors will work in Palin's favor Thursday night at Washington University in St. Louis.

At the request of the McCain campaign, the time for answers will be briefer than in the presidential debate and there will be less opportunity for free-wheeling exchanges between the candidates. This will allow Palin to stick closer to prepared responses.

The moderator, Gwen Ifill of PBS, although a veteran broadcaster, has only presided over one such debate previously: the Cheney-Edwards confrontation in 2004. In that debate, Ifill did not press either candidate with follow-ups, sticking to a fairly predictable list of questions that both men were fully prepared to address.

Sen. Biden will face a difficult task whenever he tries to forcefully challenge Gov. Palin. As closely as Palin will be watched by voters who doubt her abilities, Biden faces even tougher scrutiny by those who believe the political system still discriminates against women. Palin's team has undoubtedly noted that Hillary Clinton's most successful debating moment came in New Hampshire when she allowed her emotions to show.

Palin's poor performances in network interviews with Charles Gibson and Katie Couric certainly hurt, even prompting several conservative columnists to doubt her readiness to serve. But those very experiences - circulated widely on the Internet and cable TV - have set the bar for Palin's debate performance at what may be an all-time low. If she enters the stage without tripping; if she avoids calling Gwen "Gretchen"; if she refrains from saying "I'll get back to you," then she's already ahead on many scorecards.

One problem Palin faces is the same one that confronted John McCain in last week's debate. Economic developments have reached such a critical stage for the nation that they will certainly dominate Ifill's early questions. This was shaky ground for McCain, and may prove to be even tougher for Palin.

Palin will be at her best if any questions involve the social issues about which she is most passionate: abortion, gay rights, education, gun control. She will also be confident in addressing the nation's energy crisis.

The most fascinating prospect for Thursday's debate is summed up in the advice of some pundits: "Palin must be allowed to be Palin." They believe that her weak interview performances were the result of too much handling by the McCain campaign. So, which Sarah Palin will show up? The confident nominee who energized the GOP convention? Or, the stammering newcomer who couldn't give Katie Couric many cogent answers?

Thursday's debate may attract more viewers than the 57 million who watched Obama and McCain.

And, by the way, did I mention that Sen. Joe Biden of Delaware will also participate?

© Peter Funt. This column first appeared in The Monterey Herald.