Adams is the founder of Environics, a big market research firm, so he's got a pretty big amount of data to work with. In American Backlash, he looks at values in America. his thesis is that the big culture war in the US is not between the Republicans and Democrats or the Right and the Left. It's between the Americans who are politically engaged, who vote, and the 50-40% of Americans who don't. Red or Blue, Americans who vote are closer to each other than they are to the disengaged. Similarly, the trends both the GOP and the Dems find most troubling about "America today" are frequently lead by the disengaged.
I found the book quite interesting. If you're interested in "what Americans believe/care about/value", then this is probably up your alley. It also does a region by region analysis. I learned that, if I ever wanted to go to the US long term, I'd probably be unhappy outside of Boston. He's also got some interesting analyses of the two parties, and the core and moderate members of each.