Amazon has introduced a heat map of the political books sold in the U.S. An overwhelming lean toward red hues suggests that conservative-themed books are outselling left leaning ones coast to coast.

Amazon is quick to point out that the system isn't scientific. The map presents a rolling 30-day average of book-buying data and classifies them as red or blue depending on promotional materials and customer classifications. And there's no sliding scale. A book is either red or blue, so there's no nuance for centrists. "Just remember, books aren't votes," Amazon says on the heat map site. "So a map of book purchases may reflect curiosity as much as commitment."

Still, there's no getting around the fact that even reliably blue states like California come out in shades of red in the Amazon map. According to publishing-industry analyst Michael Norris, of Simba Information, that might be due to the right's ability to connect with its readers. "I can tell you that there are conservative imprints and conservative publishers that are just brilliant at figuring out what kind of books their audience wants to read," Norris told Wired. "There just aren't aggressively left-leaning imprints like that."

But the ability to break down top sellers by red and blue might help readers find new titles from like-minded authors and should help writers and publishers on both sides of the aisle better gauge their performance. For example, users can click on an individual state to see the top-selling red and blue books there, regardless of the state's overall color.

"Political authors can say, 'Hey, I was number 88 on Amazon's blue books' list,'" says Norris. "Authors love to see their name on a list of best-selling books."

So if you're upset because you feel your state has been misrepresented, go buy a book.