Well he had 7 years in state senate (well I guess it's 8 years by their terms or whatever, I dunno), 3 years in the US senate - though at least one of those was mostly campaigning

, but I guess you could say that for any president.
From Wikipedia:
W. Bush was governor of texas for 5 years (or 6, technically, however that works)
Clinton was attorney general for 2 years (if that counts), governor of arkansas for 2 years, then not, then governor again for 9 years (or 10)
Bush I was in the US house for 4 years, ambassador for 2 years, liason for 1 year, CIA director for 1 year, vice president for 8 years
Reagan was governor of california for 8 years
Carter was in state senate for 4 years, governor of georgia for 4 years
So there, those are the recent presidents. Depending on how you define experience (most former presidents also worked on campaigns and shit when they weren't actually in office) and how much you want to discount his current work in the US Senate, he has more political experience than Carter, Reagan, and Bush II.