Mark Sanford today lost significant support from national Republicans, shortly after his former wife's trespass allegations became public.

Attempting a comeback after the affair scandal that derailed his South Carolina governorship in 2011, Sanford is now running for the Charleston-area House seat he represented in the 1990s.

From now on, however, he'll have to do it without funding from the National Republican Congressional Committee.

"Mark Sanford has proven he knows what it takes to win elections. At this time, the NRCC will not be engaged in this special election," NRCC spokeswoman Andrea Bozek told ABC News.

The NRCC gave no reason for the decision, which comes after the trespassing allegations surfaced today.

Sanford's former wife, Jenny, said she found him leaving her house Feb. 3 through the back door, using his cellphone as a flashlight, according to court documents obtained today.

Jenny Sanford's lawyer filed a complaint with a Charleston County family court, and a judge ordered the former governor to appear at a hearing and explain why he entered the house without his former wife's permission, in apparent violation of their divorce agreement.

The hearing is set for May 9, two days after Sanford's election against Democrat Elizabeth Colbert Busch. The recent allegation followed another, in February 2011, that Sanford had "repeatedly" entered his former wife's house without permission, according to a letter from Jenny Sanford's attorney to Mark Sanford.

The former governor says he was only there this year to watch the Super Bowl with one of his sons.

"It's an unfortunate reality that divorced couples sometimes have disagreements that spill over into family court," he said in a statement today provided to ABC News. "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 watch it alone.

"Given she 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 under the light of my cellphone when she returned and told her what had happened," he added.

Sanford questioned the timing of the revelation, saying he is "particularly curious" why these allegations have surfaced weeks before the election.

Jenny Sanford told the Associated Press that the timing of her original allegation, in February, had nothing to do with his run for office.