John Greg Ganske (born March 31, 1949) is a politician from Iowa. He began a career as a plastic surgeon, but went on to serve as a Republican member of the United States House of Representatives from 1995 to 2003.
Ganske was born in New Hampton, Iowa, to parents Victor and Mary Jo Ganske, and he graduated from the University of Iowa with a B.A. in political science in 1972. In 1976, Ganske graduated from the University of Iowa medical school, where he met and married his wife, Corrine Mikkelson. Ganske worked as a plastic surgeon in Des Moines until he challenged veteran Democratic Congressman Neal Smith in 1994. Ganske campaigned in a cream 1958 DeSoto (Smith having won his first congressional race in that year), playing songs from that era. Ganske was also helped by the 1990s round of redistricting. Smith had previously represented a district that was more or less coextensive with the Des Moines metropolitan area, but redistricting had pushed it into southwestern Iowa, an area Smith did not know and that did not know him. In one of the biggest upsets in recent congressional history, Ganske defeated Smith by six points, largely by running up large margins in southwestern Iowa.