WASHINGTON – How did a former undercover CIA operative who spent more than eight years fighting terrorism get branded as a teacher at “Terror High?"

The strange ordeal for Abigail Spanberger, a Democratic House candidate, began when U.S. Postal Service employees wrongly delivered her confidential personnel file to Republican operatives.

Those operatives seized on Spanberger’s stint teaching Bronte and Shakespeare as a way to sink her campaign against GOP Rep. Dave Brat in Virginia.

Both Republicans and Democrats hurl dirt in campaigns. The involvement of the Postal Service gives the attack on Spanberger a particularly odd twist that drew outrage from national security veterans and scrutiny from investigators.

The willingness of a super PAC aligned with House Speaker Paul Ryan to publicize at least part of Spanberger's improperly released security clearance application raises questions about what information is fair game in today’s political climate.

“What is Abigail Spanberger hiding?” a voice asks in a GOP attack ad. “Spanberger doesn’t want us to know that she taught at an Islamic school nicknamed ‘Terror High,’ a terrorist breeding ground.”

The ad highlights a valedictorian’s conviction in 2005 for plotting with al-Qaida, then points to a 2003 graduate’s attempt to board a plane with a butcher knife hidden in a carry-on. The message: Spanberger was happy to cash "Terror High" paychecks.

Spanberger said her job teaching two semesters at a Saudi Embassy school outside Washington isn’t a secret, and it didn’t stop the CIA from entrusting her with two federal security clearances. It’s wrong, she said, for political opponents to exploit confidential personnel forms they shouldn’t have seen, regardless of who’s at fault for releasing them.

“It takes political gamesmanship to a whole new level that I think is beneath who we are, and frankly, I think it sends out a wrong message to public servants everywhere,” Spanberger said.

The U.S. Postal Service’s Office of Inspector General is investigating the release of Spanberger’s personnel records – a botched response to a GOP firm's Freedom of Information Act request. Spanberger worked as a U.S. Postal Inspection Service law enforcement officer in 2004 before signing on with the CIA in 2006.

Particularly troubling was the release of her security clearance application, which is supposed to be protected by the Privacy Act. The 100-plus-page document includes her Social Security number and full medical and work history. Mark Zaid, a national security attorney, said he "can't even fathom" an exception to the law that would allow a third party to get an unredacted copy.

“Someone needs to be disciplined,” Zaid said. “The system failed and when this happens, there’s no way to take it back.”

More than 200 national security veterans signed an open letter in August noting it would be “peculiar” for the first victim of such an error to be Spanberger, a Democrat running in a competitive congressional race.

“The concern is that there will be a chilling effect on people who are interested in pursuing these careers in public service if they are to believe that this information, whether by simple human error or something more sinister, could see the light of day,” said Ned Price, a former CIA analyst and National Security Council spokesman under President Barack Obama.

Spanberger’s case isn’t isolated. A small number of requests for personnel information were “improperly processed,” said David Partenheimer, a Postal Service spokesman, in a statement Aug. 30.

Partenheimer blamed “human error” and said the Postal Service would request that Spanberger's information be returned.

“We take full responsibility for this unfortunate error, and we have taken immediate steps to ensure this will not happen again,” Partenheimer said.

The Postal Service sent Spanberger’s personnel folder in July to America Rising – a conservative firm that digs up dirt on Democrats – 21 days after the firm filed a FOIA request for her employment information. The response was unusually swift. Spanberger said she asked for her own records under FOIA in December, but she still hasn’t received them.

CEO Joe Pounder said America Rising never published her personal information and offered to return it to the Postal Service. The firm shared the information with the Congressional Leadership Fund (CLF), a super PAC working to elect Republicans and aligned with House Speaker Ryan.

Spanberger said she learned what happened from a reporter, who had an unredacted copy of her security clearance application. She threatened CLF with legal action in August, but no lawsuit was filed.

Though there may be an “ethical/moral code that applies,” it’s not against the law for CLF to have the information or use it, Zaid said.

Saying the information was obtained legally, CLF released a document in August from her security clearance application, showing she worked at the Islamic Saudi Academy in Northern Virginia. A CLF television and digital ad highlighting "Terror High" began airing Sept. 6.

The ad says the school is "so dangerous," even Democratic Sen. Charles Schumer, the Senate minority leader, called in 2007 for it to be shut down. Schumer and other senators wanted the State Department to act on a federal commission's recommendation that the school be temporarily closed on the grounds that it was teaching religious intolerance. Two years earlier, Schumer called for an investigation after the valedictorian’s conviction for plotting with al-Qaida.

Schumer said he condemns anyone using his earlier comments to "attack an upstanding patriot and former CIA officer Abigail Spanberger, who had left the school years before and had absolutely nothing to do with my concerns.”

Brat, her opponent, told radio host John Fredericks on Sept. 4 that Spanberger’s Social Security number and medical records shouldn’t have been released, but her work at the school is “a big deal,” and voters deserve to know more. A Brat spokeswoman did not respond to a request for comment.

Spanberger said the substitute teaching gig was one of several short-term jobs she took while waiting to start a career in public service. She was waiting tables when a restaurant co-worker, who also worked at the school, told her she might be able to fill in for a teacher taking maternity leave.

Spanberger said she didn't teach either of the students mentioned in the attack ad. “I was teaching kids who, to my mind, were normal kids,” she said.

She checked with her CIA recruiters before taking the job in December 2002 and teaching English for two semesters. “I basically was that person who overinformed them of every decision I was making,” she said.

Spanberger went on to work narcotics and money laundering cases for the U.S. Postal Inspection Service for two years before joining the CIA in 2006 as a case officer with the Clandestine Service. She worked in Europe, on the West Coast and in Washington, focusing on counterterrorism, nuclear issues and drug trafficking.

A retired CIA officer, in a new ad Spanberger released Sept. 11, said associating Spanberger with terrorism is “laughable.”

“She focused on protecting Americans from terrorism, not sniping from the sidelines,” the retired officer, John Sipher, says in the ad.

Spanberger said public scrutiny of her background doesn’t concern her as much as the “terrible example” this sets for what people are seemingly willing to accept in politics.

“It shows a whole new level of ‘win at any cost,’ ” she said.

More:2018 midterms: GOP sees opportunity in Minnesota Trump country, despite an otherwise brutal House map

More:Midterms: How can election groups get out the vote when just half of Americans say process is 'fair and open'?

More:Trump accuses China of trying to sway U.S. midterms with retaliatory tariffs