[Servant of the Cross]

"Asked about comments that no one lacking political experience could win the White House, including those made at Larry Sabato’s Crystal Ball site (“A Cain nomination would be an aberration of historic proportions: American political parties typically don’t nominate people without previous officeholding experience for president.”), Cain pushed back.

[NeoCaveman]

American political parties typically don’t nominate people without previous officeholding experience for president

I think the last two were Eisenhower (General) and before him Wilkie (businessman)