 Hanson-Young was a candidate for the South Australian Legislative Council in the 2006 state election, ranked fourth on the Greens' ticket.Hanson-Young was elected senator for South Australia at the 2007 federal election.She was the first Greens senator to be elected in that state, the youngest person—at 25—ever popularly elected to the Australian senate, and the youngest woman ever elected to the Australian parliament (Natasha Stott Despoja was younger at her first sitting, but older at the time of her election).