COLUMBUS, Ohio (AP) -- Federal officials have investigated questionable campaign contributions to two Ohio officeholders, U.S. Rep. James Renacci (reh-NAY'-see) and state treasurer and U.S. Senate candidate Josh Mandel (man-DEHL').

Spokesmen for the two confirmed Monday they had been contacted by the U.S. Attorney's Office.

Renacci's spokesman says questioning centered on direct-marketing magnate Benjamin Suarez. The (Toledo) Blade reported in August that Suarez and 16 employees and spouses from Canton-based Suarez Corporation Industries gave donations totaling $100,000 each to Renacci and Mandel.

Federal campaign finance law prohibits a donor from contributing in someone else's name. Corporations also are prohibited from awarding bonuses or other rewards to employees in exchange for political contributions. The company has said the employees gave freely and weren't compensated.

A message left Monday with Suarez's attorney was not immediately returned.