gallup has an interesting article

2004 a "Republican year" versus 2008 a "Democrat year" had different demographics. Mostly we are talking about race here. 2012 registered voters closely resemble 2008 and not 2004. Conclusion? Gunna be a Democrat year!


a little noted line a the bottom.
electorate 2004: even numbers of Dem leaners versus R leaners. 2008: Dem leaners 12 points greater than R. 2012: R leads Dem by 3 points.

Thats a 15 point shift!
Even in my most wildly optimistic moments I would not have expected that. Phenomenal. This is going to be one for the history books