Sen. Casey Crabtree will lead the Republican caucus in his chamber of the South Dakota Legislature for the next two years. Freshly-elected GOP members of the next state Senate Friday evening at the Capitol selected the 39-year-old Madison business advocacy professional to serve as Majority Leader when the new term begins in January. Crabtree formally ran unopposed, though Big Stone City Sen. Jon Wiik had also been speculated as having interest in the position.