State Sen. Donne Trotter, a Democratic candidate in the 2nd District special election, has been charged with trying to bring a weapon onto a plane at Chicago’s O’Hare International Airport.

Trotter must appear in bond court Thursday morning to answer the Class 4 felony charge that carries from one to three years in prison, according to Cook County State’s Attorney’s Office spokeswoman Tandra Simonton.

A Transportation Security Administration agent found an unloaded gun with bullets in Trotter’s garment bag Wednesday morning while he was attempting to travel to Washington, D.C., according to local reports. He allegedly told the agent that he forgot to remove the weapon after his shift at a security job.

A favorite of local Democrats, Trotter was seen as having the inside track to win his party’s endorsement for the Feb. 26 primary. He’s a longtime state lawmaker, serving for more than 20 years.

Trotter is one of at least seven Democratic candidates vying to replace ex-Rep. Jesse L. Jackson Jr., who resigned from Congress last month. The 2nd District is heavily Democratic, and the winner of the primary will most likely come to Congress after the April 9 special election.

Jackson, a Democrat, represented the 2nd District for eight terms. He left Congress as federal investigators were probing his alleged spending of campaign funds on personal purchases.