There is a nice capsule in the WaPost today summarizing Alan Abramowitz's APSA presentation that the Tea Party has about 90% of Republicans identifying with, but almost no influence on members of House getting elected (and they use new 2010 data for this). Furthermore Abramowitz finds that those who identify themselves as Tea Party members are more likely to see Democrats as evil demons than Republicans of yore. The APSA article is very readable even for those who do not have much of a statistical background. By the way one of the best books I (The Whites of Their Eyes) have read in the last year compares the "real tea partiers to those of today. At any rate the WaPost article is a good example to point out to students of the difference between the outlier stories written in newspapers and political scientists who want to prove everything statistically and do not have a political point to make in their paper.