Nate Silver has two quite interesting posts ("here":http://fivethirtyeight.blogs.nytimes.com/2011/08/13/why-ames-actually-matters/ and "here":http://fivethirtyeight.blogs.nytimes.com/2011/08/13/youve-just-won-the-ames-straw-poll-what-are-you-going-to-do-next/)