A former C.I.A. officer running for Congress accused a super PAC aligned with Speaker Paul D. Ryan on Tuesday of improperly obtaining her entire federal security clearance application — a highly sensitive document containing extensive personal information — and then using it for political purposes.

Abigail Spanberger, the Democratic candidate challenging Representative Dave Brat of Virginia, sent a cease-and-desist letter to Corry Bliss, the executive director of the Congressional Leadership Fund, which has raised more than $100 million to help Republicans in the midterm elections. She demanded that the super PAC destroy all copies of the form and agree to not use the information in any fashion.

“I write as a former civil servant and as an American, in shock and anger, that you have tried to exploit my service to our country by exposing my most personal information in the name of politics,” she wrote.