Farrow served on the Elm Grove, Wisconsin Board of Appeals from 1971–1974 and the Village Board from 1976–1987, spending the last five years of her tenure as president. After her time with the Village Board, Farrow was elected to the Wisconsin State Assembly, and later the Wisconsin State Senate, from a district comprising most of Waukesha County, Wisconsin. The first female lieutenant governor of Wisconsin, Farrow was appointed to the position after then-Lieutenant Governor Scott McCallum was elevated to the office of governor upon the departure of Gov. Tommy Thompson to join the administration of George W. Bush in January 2001.