Why Democrats are bringing up Mark Sanford’s affair now

For weeks, the relationship that has loomed over the South Carolina special House election has largely been avoided in the race itself. While Democrats have hinted at  former governor Mark Sanford's affair in ads attacking his disappearance and air travel, it wasn't until Monday -- a week before the election -- that the House Majority PAC approached it head on:

The House Majority PAC spot came hours after Democrat Elizabeth Colbert Busch referenced the affair in her only debate with Sanford, more obliquely. The ad is not subtle at all. "He skipped town to be with his mistress on Father’s Day," says the narrator, who describes herself as a female Republican. "Mark Sanford just doesn't share our values." Ethics are mentioned, but only briefly.

Party strategists told The Hill in early April that they believed "there's little to gain from harping on Sanford's infamous extramarital affair because voters know all about it." Instead they planned to focus on the state ethics charges against him and his alleged misuse of taxpayer funds.

This territory is actually a place where Sanford is comfortable -- he's discussed his relationship with now-fiancee Maria Belen Chapur repeatedly and at length. In the Republican primary for the seat, he managed to inoculate himself from this attack by arguing that Christians should forgive.

What changed?

To start with, there's the recent revelation of a trespassing complaint filed by Sanford's ex-wife, news that prompted the National Republican Congressional Committee to drop support for his bid.

"The trespassing charge brought it to the forefront" again, said one Democratic strategist.

Second, the race is almost over. Colbert Busch has shown herself to be a serious challenger, and Democratic ads have repeatedly made a case against Sanford on ethics grounds. In that context, criticism of his personal behavior might not seem so desperate.

It could be a sign that a week out, the race is closer than a recent automated poll from the Democratic Public Policy Polling firm suggests. "I think they realize that this is not a slam dunk win for her, and their going to have to be aggressive here at the end," said in-state Republican strategist Richard Quinn.

Polling must show that the issue resonates with Republican women -- whether because of the trespassing news or because they never got over the affair in the first place. South Carolina's 1st district is red, and the only way Colbert Busch will win is if she peels off GOP women.

"Both sides appreciate the fact that the turnout model in this district by gender is 56 percent women to men," said Walter Whetsell, a South Carolina Republican consultant. Sanford, he said, might be at a "tactical disadvantage" because Colbert Busch can let a super PAC make this direct emotional appeal -- while Sanford is on his own.

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