Sioux Falls, S.D. (AP) Midwestern lawmakers and farmers are shifting the attention of a railcar shortage problem to Washington with proposed legislation, a committee hearing and meetings with decision makers. South Dakota Sen. John Thune says he's co-sponsoring legislation to give the national surface transportation board more efficiency and authority. Among the proposed changes: increase the STB's investigative authority, so it can do its own investigations instead of waiting for a complaint; improve rate review timelines; and increase the number of members from three to five. The commerce committee will also hold a hearing Wednesday that will examine rail service backlogs nationwide. And Farmers Union members from around the country are pressing the rail issue with members of congress, staffers in the United States Department of Agriculture and White House, and the STB.