In Gallup's tracking and in the latest CBS/New York Times survey, Sen. Barack Obama seems to have recovered remarkably quickly from whatever fallout fell upon him from the coverage of Rev. Jeremiah Wright's public tour. USA Today's latest poll -- also, confusingly, from Gallup finds the exact opposite: that a survey taken Tuesday through Saturday shows Clinton leading Obama by seven points among Democrats and Democratic-leaning independents. What's going on here?

A lot of fluidity within stability. A good chuck of Democrats -- about 15 of out every 100 -- seem to be very much influenced by the weathervane. It's hard to imagine that these folks truly shift their preferences from day to day. It's more likely that they shift their preferences based on how they perceive the likely outcome of the election -- we are in a media environment thoroughly saturated by talk of that non-dictionary word, electability.

Analysts also tend to overstate the significance of the bouncing around of numbers, as's Mark Blumenthal reminds us regularly. There's a lot of variation within a small narrowing trend -- a trend we clearly see reflected in poll-of-poll averages.