McLean County Judge Paul Lawrence reinstated McDade to the ballot for the upcoming municipal election.
McDade's eligibility came into question when her opponent Matthew Koetters found errors on her nominating petitions.
The errors included no specification about which ward McDade is running for and an incorrect date of the February primary.
The Bloomington Election Commission upheld Koetters' challenge, which McDade appealed.
Lawrence overturned the commission's decision Monday, saying the commission violated the state's transparency laws for open meetings of government bodies.
As a result, Lawrence ruled McDade's due process rights were violated.