Rep. Aaron Schock (R-Ill.) has an opponent, as Democrat D.K. Hirner entered the race Thursday.

Hirner has served as Executive Director of the Illinois Environmental Regulatory Group for the last four years, a position she also served in around the turn of the century. She has also been a top official in the administration of two Missouri governors and has spent time as a college professor.

“I believe we need a representative for the 18th district that is serious about addressing the issues our country faces today,” Hirner said in a statement. “I look forward to speaking with folks across the district during this campaign about the issues that matter most and working with them for a better future.”

Schock won easily in an open-seat race in 2008, successfully battling the Obama wave in the president's home state. He took 59 percent of the vote, as his Peoria district went 50-48 for Sen. John McCain (R-Ariz.). He is not considered among the more vulnerable freshmen.