The known unknowns

From Ambers:

1. The Obama turnout machine (size, scope)
2. Racism
3. Secret Republican Obama Admirers (The Goodbye To All That Effect)
4. The demographic composition of undecided voters; the ideological composition of these voters; the actual size of this group of voters
5. Whether people assume Obama will win and therefore don't feel compelled to vote for him (the Democratic overconfident effect)
6. A few ballot initiatives (Florida, Colorado)
7. The pro-or-anti-Palin vote (suburban women, jazzed conservative base)
8. The Bradley effect (whites lying to pollsters and saying they have NO opinion when they actually support the white candidate)
9. The Wilder effect (whites lying about supporting the black candidate)
10. The Van Wilder effect (young voter surges in red states like Indiana)
11. Media backlash effect (?)
12. The weather -- (supposedly gorgeous)
13. The Republican depression effect (the counter to the Democratic overconfidence effect)
14. Independent-leaning fiscal conservatives turning Libertarian
15. whether African Americans vote at Census + 0, C + 1, C + 2....
16. The effect of the last-minute McCain television advertising surge
17. Whether such a thing as the Howard Dean-Red-Cap effect exists (i.e, scary college kids trying to get older adults out to vote...and they're resentful)
18. the idea of a unified, uni-polar Congress excites people, turns people off, or doesn't really matter

By #14 does he mean Barr voters? I think so. These are people who would normally have voted Republican (were it not for their disastrous fiscal record over the past 10 years) so each one counts as 1/2 an Obama vote.