Republican congressional candidate Samuel Wurzelbacher, who's better known as Joe the Plumber, campaigns Friday, Feb. 24, 2012, in Rocky River, Ohio. Former presidential candidate Herman Cain joined Wurzelbacher on the campaign trail Friday. Wurzelbacher is facing Steve Kraus, a real estate agent from Sandusky, in the state's March 6 primary for the 9th Congressional District. (AP Photo/Tony Dejak)

Republican congressional candidate Samuel Wurzelbacher, who's better known as Joe the Plumber, campaigns Friday, Feb. 24, 2012, in Rocky River, Ohio. Former presidential candidate Herman Cain joined Wurzelbacher on the campaign trail Friday. Wurzelbacher is facing Steve Kraus, a real estate agent from Sandusky, in the state's March 6 primary for the 9th Congressional District. (AP Photo/Tony Dejak)