10/08/2008 04:13 pm ET Updated May 25, 2011

Polling's Perfect Storm

My column this week reviews the three big sources of worry among pollsters and others about the accuracy of polling this fall: the potential that pollsters are missing voters in "cell phone only" households, the potential that "likely voter models" may be missing certain types of voters and the worries about the Bradley-Wilder effect.

We have covered all of these topics before and my plan is to devote a column to each over the next three weeks because while everyone is speculating, we probably know more than we think we do empirically, about the potential for error from all three sources.

And since some will react to the title without clicking through, I blog my own spoiler. Here's the last paragraph of the column:

Meanwhile, we can probably dispense with the "Perfect Storm" analogy. In the movie of the same name, three different weather-related phenomena combined to produce a storm of exceptional severity. In this case, as Democratic strategist Joe Trippi pointed out in September, the potential polling foibles may work in opposite directions and "cancel each other out." A return of the Bradley-Wilder effect would work to McCain's benefit, while an underrepresentation of younger, African American or "cell-phone-only" voters will likely benefit Obama.