David Nicholas Winderlich (born 18 January 1964), is an Australian teacher, public servant and politician who in February 2009 was the Australian Democrats nominee to fill a South Australian Legislative Council casual vacancy in a joint sitting of the Parliament of South Australia following the January 2009 parliamentary resignation of the incumbent Democrats member Sandra Kanck. Becoming an independent after nine months, he was the last Democrat to have sat in any Australian parliament. He was not re-elected at the 2010 election.
Winderlich announced that, as an independent, he would focus on three policy areas: governmental reform, rights and freedoms, e.g., for bikies, and a sustainable approach to the management of water resources in South Australia. In particular, he was opposed to the Port Stanvac Desalination Plant and to the Wellington Weir proposal.