John Joseph Madigan (21 July 1966 – 16 June 2020) was an Australian blacksmith and politician. He served as a Senator for Victoria from 2011 to 2016. He was elected to the Senate at the 2010 federal election as a member of the Democratic Labour Party (DLP). He resigned from the DLP to become an independent in September 2014, and later launched "John Madigan's Manufacturing and Farming Party" in 2015. He failed to be re-elected at the 2016 double dissolution election, and the Manufacturing and Farming Party was voluntarily deregistered on 13 September 2016.