. >> lawrence wright: texas is an urban state.st, top-ten cities are in texas. and number 11 is austin. >> wertheim: lawrence wright is a longtime resident of austin, and the author of the book, "god save texas." he characterizes the state in terms of two different radio frequencies. you've divided texas into what you call a.m. texas and f.m. texas. explain that. >> wright: well, i think a.m. texas is what most people outside of texas think the state is. a.m. texas is, you know, rush limbaugh. >> wertheim: social conservative. care about their gun rights. >> wright: very much so. evangelicals and so on. and yet, there's a side of texas that many people don't really understand, and that's the f.m. texas, which is more urban, progressive, more like other cities in the country. >> wertheim: the big question: which frequency will have the greater signal strength on tuesday? >> wright: i think that a lot of the tea party political figures in power right now see over the horizon. and what they see is a big change coming their way. and t