Of course not. He's making way for Allen West.
With DeMint, Pence, Christie and Thune gone, and the fact only Romney and Huckabee are competitive (and barely, at that) in a hypothetical general tells me the GOP has a horrendously weak field.
Good people see what happened to Palin. They're simply not willing to subject themselves and their families to the political meatgrinder.
Thune would be a good VP candidate.