The strategy appears to have paid off.
4. Location, location, location
Macro: The 1st Congressional District is GOP country. Mitt Romney carried the district by 18 percentage points in last November's presidential election. And Rep. Tim Scott was reelected by 27 points before he was picked by GOP Gov. Nikki Haley to fill the Senate seat vacated by Sen. Jim DeMint, who stepped down to take over as the head of the conservative Heritage Foundation.
Even a candidate with serious political baggage like Sanford was able to win.
Micro: Sanford won all five counties in the district. He won big where he needed to, in the conservative counties of Berkeley and Dorchester, taking around 60% of the vote. He carried the district's second most populous county, Beaufort, by 6 percentage points. Some Democrats hoped that older voters in that county, which includes Hilton Head, would be turned off by Sanford's affair.
Sanford narrowly carried his home base of Charleston County, where the most voters were at stake. That was also Colbert Busch's best hope.
5. Money doesn't always matter
Colbert Busch's campaign outspent Sanford's operation in the closing weeks. And the DCCC and House Majority PAC combined spent around $900,000 to try to defeat Sanford, who received far less support from outside groups. Money matters in campaign politics, but it's just one factor in determining a race.