SPRINGFIELD - Democratic congressional candidate Colleen Callahan announced plans Tuesday to begin airing television ads aimed at Republican Aaron Schock's apparent backdating of documents for his father while serving as a notary. | Local election page

The latest salvo echoes Callahan's recent criticisms of Schock, even though Peoria County's prosecutor Monday said Schock wouldn't be further investigated over reports he signed off on inaccurate documents.

Schock, a state representative from Peoria, has called the problem a "clerical error."

Schock and Callahan, along with Green Party candidate Sheldon Schafer, who works as a museum vice president in Peoria, are vying for the 18th Congressional District seat being vacated by retiring U.S. Rep. Ray LaHood, a Peoria Republican.

Callahan's ads come as Schock was touting endorsements Tuesday from 116 mayors in the Central Illinois district.

"We rely on our congressman's office for important federal assistance," Forsyth Mayor Hap Gilbert said in a statement. "I am confident that Aaron Schock is well prepared to take up where Congressman LaHood leaves off without missing a beat."

Schock has been airing campaign ads for months, often promoting his work as a member of the Illinois House. Callahan's ads have been more pointed and have criticized Schock.

Callahan, a communication consultant from Kickapoo, defended the spots, contending her campaign wasn't overly negative.

"What we have said is an actual fact," she said.