But what's going on becomes clearer when you look at how polls work and at what's happening with the electorate this campaign season. One of the first things experts point out is that polls are not meant to be definitive predictors of an election's outcome. Instead, they're snapshots of where a race stands at the moment a survey is taken. Three times, the leads have been outside the poll's margin of error - signs of significant shifts. The other five shifts have produced leads within the margin, meaning there was a small chance the leads weren't actual.
Polls have margins of error, often of several percentage points.
A margin of plus or minus 3 percentage points means candidates' results could be three points higher or lower. When one candidate started going up, all polls eventually went that way. When one candidate was going down, all polls eventually showed that as well. State polls also have been volatile. Double-digit leads for Gore in Pennsylvania, Illinois, New Jersey and California have fallen to single digits.