A source at the committee said it was caught off guard by the trespassing complaint, filed in February, which is why the committee decided to get out of the race.
The committee's official statement from spokeswoman Katie Prill was less harsh.
"Mark Sanford has proven he knows what it takes to win elections," she said. "At this time, the NRCC will not be engaged in this special election."
The move means Sanford loses access to powerful messaging and fundraising tools as he takes on Democratic candidate Elizabeth Colbert Busch. Some recent polls have shown Sanford and Busch essentially tied. Busch also has mounted a significant fundraising push with the help of her celebrity brother, Comedy Central host Stephen Colbert.
Walter Whetsell, a veteran Republican political consultant based in South Carolina, called the National Republican Congressional Committee's decision to walk away from Sanford's candidacy a "de-endorsement."
"The Congressional Committee has a long history of investing their financial resources with candidates they believe can win," he said. "That is their No. 1 criteria — viable candidates."
But other Republican experts insist the political laws of demographics are too strong to keep Sanford out of office, noting the 1st District was drawn by a Republican-dominated General Assembly to ensure a GOP victory.
"If the district holds true to its demographics, you've still got to think that it should lean in his favor," GOP strategist Richard Quinn of Columbia said.
National pundits now are more wary of the race's outcome, with the Cook Political Report listing the race as a "toss-up," saying the NRCC's decision "in effect, relegat(ed) former Gov. Mark Sanford to 'Todd Akin land' " — a reference to the former Republican U.S. Senate candidate from Missouri who lost GOP support after making controversial comments about rape.
Once thought to be a possible GOP presidential or vice presidential candidate, Sanford stunned South Carolinians in 2009 by vanishing from the state for five days to visit his Argentine mistress, Maria Belen Chapur, over Father's Day weekend. Sanford confessed to his affair when he returned, and he and Jenny Sanford subsequently were divorced.
Colbert Busch's campaign declined to comment again Wednesday on Sanford's woes.
Other South Carolina Democrats said history stops them from thinking a Colbert Busch victory is imminent.
"I never get too confident anywhere in South Carolina as a Democrat. But I think yesterday it was a 50-50 race, and today I think it is more like a 60-40 race in her favor," said Tyler Jones, a Charleston-based Democratic political consultant. "(Colbert Busch's) campaign is not going to take this for granted, and they are going to keep working hard to get their message out."
Sanford took a beating in the national media Wednesday, with multiple outlets reporting Sanford repeatedly had violated the terms of his divorce agreement — the most significant being a trespassing charge filed by Jenny Sanford stemming from an incident on Super Bowl Sunday. Sanford is due in court to answer that complaint just two days after the May 7 special election.
In a news release, Sanford said he went to his ex-wife's home without her permission on Feb. 3 so he could watch the second half of the Super Bowl with the couple's 14-year-old son "because, as a father, I didn't think he should watch it alone."
The Sanfords' divorce settlement says neither can enter the other's home without permission.
Sanford said he tried to reach Jenny Sanford to explain the situation to her but was unsuccessful because she was out of town. Sanford said he "met her at the back steps under the light of my cellphone when she returned and told her what had happened."
The trespassing charge was reported first Tuesday night by The Associated Press, citing court documents.
In his statement Wednesday, Sanford said: "There is always another side to every story, and while I am particularly curious how records that were sealed to avoid the boys dealing with embarrassment are now somehow exposed less than three weeks before this election, I agree with Jenny that the media is no place to debate what is ultimately a family court matter, and out of respect for Jenny and the boys, I'm not going to have any further comment at this time."
A Sanford campaign spokesman did not respond to multiple requests for comment from The State.
Tuesday night, Jenny Sanford told The State that Sanford's election prospects were not a concern to her, adding she is "focused on raising my children."
Meanwhile, The Washington Post reported Wednesday that tensions between the Sanfords rose after Chapur, now Mark Sanford's fiancee, attended Mark Sanford's April 2 GOP runoff victory party. Two of Sanford's sons, with Jenny Sanford, also were at that party. The Post reported that Jenny Sanford texted it, saying, in part, "both boys were quite upset and visibly so."
Mark Sanford sent an email to supporters Wednesday afternoon, saying, "It has been a rough 24 hours" and that "divorce is tragic at many levels." He included his phone number for people to call him if they have any questions.
"I think I need to stay focused on the verse a friend gave me last night: 'God did not give us spirit of fear, but of power, love and a sound mind,' " the former governor wrote. "I hope to apply those concepts over these last two weeks of the race and while political opponents will use this to distract from issues that matter to Lowcountry voters, we know what we have to do to win. Quite simply to continue to get our message out about limiting government and empowering people. At the end of the day cutting taxes, debts and deficits and strengthening the marketplace leads to jobs so important to people here on the coast."
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