There's a really cool poll from the The Washington Post and the Kaiser Family Foundation that (without looking) doubtless has gotten a lot of play on Kos. I'm not even going to try. This is just a bookmark; anyone that cares to comment, please limit it to pointing to other analyses on Kos and elsewhere of their results. Or doing such analyses as separate diaries, and linking to them; whichever.
First good entry point: Blue, Red, and White factions: Democrats, Republicans, and Independents.
And an entry point to the polling data; the "detailed view" links tend especially informative.