South Dakota Senator John Thune looks like a Republican President straight out of central casting. Tall, tan and chiseled, Thune entered the national discourse in 2010, widely touted as a candidate for the GOP presidential nomination. But despite encouragement from his cloakroom pals Senators Mitch McConnell and Lindsey Graham, Thune didn't spark much excitement in the polls, and he took his name out of contention on Feb. 22.