As an exercise, see if you can find the signs that the author of this article is a DEMOCRAT (besides the fact that he works for CNN.com, I mean).
Ready?
Scroll down for the answer....
Here are the two sentences that gave him away:
"2) just how geographically isolated we are, politically speaking."
Only the Democrats are "isolated" in small enclaves known as "major cities". Republicans are the normal, working class Americans living all over the country -- as evidenced by all the RED on the map. And it matches the reality on the ground: I don't feel like my beliefs (mostly common sense) are rejected by most people on the street. On the contrary, I think we're the "silent majority".
"Today, there are 118 seats with a PVI of D+10 and 133(!) seats with a PVI of R+10."
You can tell that 133 seats really bugs him -- he had to put in a little exclamation point, as if he's shocked that SO MANY people can be stupid Republicans.