I don't really know Tenn. politics, but I'm surprised to see Shelby go for Alexander and Davidson go for Carr, since I thought the white areas in/near Memphis, were far more conservative than the white areas in/near Nashville.
In Shelby County, Lamar is our BFF
Actually there are a couple of reasons --
1) Shelby County's suburbanites tend to be more traditional social conservatives while those in middle TN are more closely aligned the new rage of the tea party. Mike Huckabee and Right to Life endorsed Lamar.
2) Memphis has a relatively significant Republican population for a major urban city, and these folks are pro-business and a bit more moderate. I haven't seen precinct results yet, but I'd be surprised if Lamar wasn't racking up high margins in East Memphis.
All that being said, Carr got more votes than I thought he would in Shelby, and his percentage was deflated by Flinn.
In the general election Lamar should do well again in big Shelby. In 2008 he got nearly a quarter of the African-American vote, and another quarter refused to vote for his opponent over him.