Manning, a former Army private imprisoned for sharing classified government documents with WikiLeaks, tweeted a photo on Wednesday evening showing her displaying her filing paperwork.
The whistleblower, 30, announced her intention to run earlier this month and released her first campaign video on Sunday. Manning is one of five Democrats who have filed to run in the race, and will face off against incumbent Sen. Ben Cardin (D-Md.), the highest-ranking party member on the Senate Foreign Relations Committee.
“We don’t need more, or better leaders,” Manning says in the clip. “We need someone willing to fight. We need to stop asking them to give us our rights. They won’t support us, they won’t compromise.”
Manning was released from prison in May 2017 after serving seven years. Her sentence was commuted by former President Barack Obama last January.