From left, Jim Risch, Josh Roy, Denny LaVé, Joe Evans. (Risch photo by Otto Kitsinger for the Idaho Capital Sun; Roy, LaVe, Evans | Courtesy of the candidates BOISE (Idaho Capital Sun) — Three Republican challengers are seeking to unseat incumbent Idaho U.S. Sen. Jim Risch. Joe Evans, Denny LaVé, Josh Roy and Risch will all appear on the May 19 Republican primary election ballot. The winner of this primary contest will face the winner of the De…