Please look up the elected offices that prior presidents have occupied before serving as president. Actually, here, I'll do it for you: Bush, governor of Texas; Clinton, governor of Arkansas; Bush, vice-president under Reagan and extensive employment history in the executive branch; Reagan, governor of California; Carter, governor of Georgia; Nixon, vice-president under Eisenhower.
The lone exception over the last 40 years is Gerald Ford. Note that Gerald Ford was not elected into the vice-presidential office, nor did he win his own presidential election against the former governor of Georgia. Ford was a former Representative.
The idea that the public prefers voting into executive office those who've held similar positions is a generally accepted idea of political science. What those candidates believe is important, but it's extremely difficult to discount this electoral trend.
Just because traditionally it goes to governors that is not going to make me change my mind about Duncan Hunter. He represents the way I feel on ALL issues, which is nice for a change.