MADISON, Wis. (AP) — The Republican candidates for U.S. Senate plan to debate for the first time April 26 in Pewaukee. The conservative group Americans for Prosperity-Wisconsin announced the debate on Thursday. It says both state Sen. Leah Vukmir and Delafield businessman Kevin Nicholson have agreed to debate. They will face each other in the Aug. 14 primary with the winner advancing to take on Democratic Sen. Tammy Baldwin.