He's accused of trying to steer a Chicago Public Schools contract to a Cleveland-based company in exchange for donations to the campaign of former Alderman Danny Solis.
Prosecutors said Caldero offered Solis a $100,000 bribe from a business owner in exchange for Solis' help in getting a street and park renamed. This happened as Solis was cooperating with the FBI.
Caldero said in a statement Wednesday: "I never offered anything to a public official or a government official."