CNN — (CNN) -- Republican Mark Sanford's bruised campaign is fighting to bounce back in the South Carolina special congressional race after having a few rough days last week.
The campaign released a new television ad Tuesday attacking Democratic opponent Elizabeth Colbert Busch for accepting contributions from labor unions. The six-figure spot will run on broadcast and cable in the Savannah and Charleston markets, according to the campaign.
With the May 7 special election just weeks away, Sanford's team was dealt a blow last week when court documents revealed his ex-wife, Jenny, had filed complaints against Sanford for trespassing on her property. He's scheduled for a court appearance two days after the election.
Not long after the story broke, the National Republican Congressional Committee announced it was pulling out of the race-and national Democratic groups announced they were throwing more money into the contest for the 1st Congressional District, a longtime Republican stronghold. In fact, Sanford represented the same district in the House before being elected South Carolina governor in 2002.
In the new commercial, first reported by Politico, a narrator says Colbert Busch is "fighting for big labor" and has been "funded by labor union special interest money."
"Labor's voice. Pelosi's voice," the ad continues. "Not our voice."
Labor is a sensitive topic in South Carolina, as the Palmetto State has been fighting back labor protests to bring a new Boeing plant to the state. The company, however, announced earlier this month it was expanding in South Carolina, a big victory for labor union opponents.
When Colbert Busch praised Boeing's move, Sanford's campaign was quick to point out that she had accepted contributions from unions that fought against Boeing's plant in North Charleston.
With their new ad, it seems Sanford's campaign finds it best to keep pushing on the union front in the final stretch of the race.
In another sign Sanford is struggling to stay out front, he released a full-page ad Sunday in Charleston's Post and Courier explaining again the trespassing incident in a lengthy letter to voters.
"I was returning a son from neighborhood Super Bowl party. I did, indeed, watch the second half of the Super Bowl at the beach house with our 14-year-old son because, as a father, I didn't think he should sit alone and watch it. Given Jenny was out of town, I tried to reach her beforehand to tell her of the situation that had arisen, and met her at the back steps and told her what had happened," he said.
Agreements from their divorce prohibited the couple from visiting the other's property without permission. During his second term as governor, Sanford admitted in 2009 he was having an extramarital affair to an Argentina woman, who's now his fiancée. He and Jenny got divorced a year later.
In the full page ad, Sanford gave his cell phone number if voters had further questions and noted that national Democratic groups were pouring more money into the race.
"I need your help, and I need it now," he said, comparing his campaign to those trying to defend the Alamo in 1836. "I'm outnumbered right now but will fight to the end toward freedom and financial sanity in Washington so important to sustaining it. I'd ask you to cross the line and fight with me."
Also part of their offensive strategy, Sanford is highlighting that Colbert Busch, sister of satirist Stephen Colbert, has only accepted one debate invitation. His campaign is calling for television stations to broadcast the showdown, set for April 29. And Sanford's team proposed 15 joint appearances with Colbert Busch this week, but she indicated she would not be participating.
"If we had a longer period of time, for sure (we'd do more debates)," said Colbert Busch, according to The Greenville News. "I want to get to know the district. I already know Mark."