Former Wisconsin Gov. Tommy Thompson, the Republican candidate for the U.S. Senate, speaks on Wednesday, Aug. 15, 2012, to HUSCO International Inc. employees during a campaign appearance at the company's Waukesha, Wis., facility. Mr. Thompson will face Democratic Rep. Tammy Baldwin in the November election. (AP Photo/The Waukesha Freeman)

Photo by: Charles Auer

Former Wisconsin Gov. Tommy Thompson, the Republican candidate for the U.S. Senate, speaks on Wednesday, Aug. 15, 2012, to HUSCO International Inc. employees during a campaign appearance at the company's Waukesha, Wis., facility. Mr. Thompson will face Democratic Rep. Tammy Baldwin in the November election. (AP Photo/The Waukesha Freeman)