"I'm winding her up," Dempsey told the Red Wing Republican Eagle.
Dempsey was elected to the House in 1992 and re-elected six times.
Dempsey's decision has set off a scramble among contenders for his seat. Two early names to emerge on the GOP side are Gary Iocco and Teresa Whitson, two Red Wing-area residents. Also considering a run from the DFL is Sandy Wollschlager, who ran unsuccessfully against Dempsey in 2002 and 2004.