Transcript for Close Congressional Race in South Carolina
And now on to politics, an election tomorrow that defies all expectation. A former governor who left office after an affair that became a late-night running joke, running against the sister of a famous comic. Jeff zeleny dissects the exciting vote beginning in south carolina in hours. Reporter: A second ghans south carolina. Mark sanford, the state's former governor, tearfully resigned to be with his argentinian lover. Now he's his feeiancey and he's running for his old congressional seat. He stopped by a tire shop today in buford. Some people have forgiven. He was great as a governor. I think he'll be good at anything else. We should give him a chance. Reporter: Some have not. I don't think his ethics are worthy of being elected to office. Reporter: His opponent in the special election on tuesday is elizabeth colbert bush, sister of comedian steven kolber. It's a deeply republican district. As a successful businesswoman making her first bid for public office she's keeping true to her slogan. It doesn't mean you take the money we saved and leave the country for a personal purpose. Reporter: Her brother has been beating up on sanford late nights on comedy central for years. You are incredibly boring. Reporter: The outcome will not determine the balance of power in washington, but it will decide whether mark sanford, first elected during the 1994 gop wave has a second act in politics and a chance at redemption. Jenny sanford says she wants to stay out of the race, but she's not been out of the picture. She accused her ex-husband of trespassing, sneaking into their house to watch the super bowl with one of their sons. I think a future for him would be a challenge. But never say never in politics. I don't know. Reporter: But she's not said if she's voting for him. Jeff zeleny, abc news, washington.
This transcript has been automatically generated and may not be 100% accurate.