Two polls (CNN/ORC and Gallup/USAToday) taken on same days (9/5-7/08), one tied, one 10-pt gap.

Guess which one's the outlier?

http://politicalticker.blogs.cnn.com/2008/09/08/cnn-poll-race-dead-even
http://pollingreport.com/wh08gen.htm

consistently tied or behind? Given how many Republicans have switched to Obama, and there hasn't been a corresponding Democratic exodus to McCain, the numbers just don't add up at all. Seems like the media stirring shit up, to me...

The CNN poll showed that Obama had no bounce and now shows that McCain had no bounce.

The gallup poll has been so thouroghly discredited among the polling community because of its weighting it is not take seriously - however it should be assumed that McCain did get some bounce out of the convention.

This, to justify the increased enthusiasm of the GOP base.

Keep in mind that David Plouffe said national polls mean nothing and that Gallup in particular is "pure garbage."

Plouffe said what Team Obama looks at are internal battleground state polls and only the underlying fundamentals
at that.

Independents are solidifying this early????

Bullshit.

tracking poll shows that it's only up 5.

Which Gallup poll should we believe?

Polls proving unreliable? How can that be? Heck - they were so accurate during the primaries?

representative of likely voters on Election Day.

From poll to poll, the composition of the half or less of those chosen randomly who actually respond fluctuate. Thus virtually all polling organizations except Gallup re-weight their sample statistically so it looks like the projected electorate on next Election Day on "party ID", ethnicity, gender, income, and other factors known to be strongly correlated with "candidate preference".

Gallup does not weight by "party ID", thosgh it does weight by other factors. And its own results from this weekend show a dramatic jump in "enthusiasm" for one's party's candidates. This is a big problem and possible source of BIAS for Gallup's methodology, since Republicans temporarily "energized" by the theatrics at St. Paul may be much less likely to refuse a Gallup interview, though no more likely to show up at the polls in November. Also, during R convention week, Republicans are more likely than Democrats and Independents to be sitting home in front of the TV and thus be available to get the call from Gallup.

Exactly the same thing happened four years ago after the Republican convention. Gallup and Rasmussen (then using the Gallup methodology) showed big jumps for Republican candidate preference, while other organizations weighting by party ID showed tiny gains for the Rs. Rasmussen then blamed their error on the methodology they used and switched to the "weight by party ID" camp. Don't be alarmed; the next Gallup poll should show a dramtic swing back toward Democrats.

See http://www.depts.ttu.edu/hs/hdfs3390/weighting.htm .

While I would trust Gallup's likely voter model on election eve, there is too much convention noise right now to get a clear picture.

Their registered voters number is more in line with other major pollsters.