Sanford acknowledged he "failed very publically" but said he had done a lot of soul searching since then. He added, "Not since Jesus Christ was here has there been a perfect man or woman."
He said that after Scott was appointed, people kept encouraging him to run.
Sanford said they told him "here is your chance for you to learn, not only from your experience in Congress and the governorship, but more significantly what you learned both on the way up and the way down and apply it to what is arguably one of the great conundrums of our civilization, which is how do we get our financial house in order."
One of those in attendance at the debate was Barbara Boilston, a 49-year-old paralegal from Charleston. She talked about Sanford's indiscretions.
"I believe he has come full circle," she said. "I believe he has found peace with God. If God forgives, I forgive, and we should go forward and put this man back in office."
Bostic said earlier Tuesday that he liked his chances as he visited with voters in a suburban Charleston precinct.
"People dismiss us," the attorney and retired Marine said. "But we believe strongly the best way to win elections is through relationships and we have worked really hard to do that."
Bostic himself did not vote in the GOP runoff on Tuesday because he can't.
His residence near Ravenel, S.C., is in the 6th Congressional District, represented by U.S. Rep. Jim Clyburn, about 1,500 yards from the 1st District line. Bostic's law office, other property, church and children's schools are in the district. Under federal law, to run for the U.S. House, one only need to be a resident of the state in which the district is located, not the district itself.
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