Race filings demonstrate that Manning, 30, presented her appointment to the Federal Election Commission on Thursday as a Democrat.
Chelsea Manning, the transgender woman who was convicted of disclosing classified military information to WikiLeaks, has filed a statement to run for U.S. Senate in Maryland.
Democratic Senator Ben Cardin was elected in 2006 to that seat and is expected to run for re-election this year. At the time, Manning was a 22-year-old United States Army private named Bradley Manning, and she served seven years of a 35-year sentence.
Manning had been working as an intelligence analyst in Iraq.
Miss Manning was arrested in May 2010, while serving with the USA army in Iraq, after she confessed to a computer hacker, Adrian Lamo, that she was the source of Wikileaks' documents.
Manning was convicted in 2013 by a military tribunal under the Espionage and Computer Fraud and Abuse Acts for releasing over 700,000 documents to WikiLeaks.
In 2013, Manning was convicted for 35 years for the largest leak of classified documents in U.S. history, which included military information about the war in Iraq and Afghanistan and State Department cables.
President Barack Obama granted clemency to Manning before leaving office.