The Gallup tracking poll … gyrated wildly in the weeks leading up to the  election, sometimes showing sizeable leads for Bush, sometimes showing sizeable leads for Gore, and sometimes showing a close race. Indeed, only 10 days before Election Day, Gallup’s tracking poll had George Bush leading Al Gore by 13 points — similar to Bush’s lead over John Kerry [among likely voters] in Gallup’s most recent 2004 poll.
That’s about 14 points off for Gallup, considering the final vote count in 2000. A similar margin this time puts Kerry in the White House.
Keep an eye on Ruy Texeira for thoughtful (if partisan) insights into what polls actually mean. They’re not as simple as they sound.