The Australian Greens will launch a TV advertisement featuring former Liberal prime minister Malcolm Fraser endorsing Greens Senator Sarah Hanson-Young.
Airing for the first time on Sunday night, the 30-second commercial features the former PM endorsing the senator at a public forum in Adelaide earlier this month.
"I don't know how many Australians would trust either political party with total political power at the present moment," Mr Fraser says in the ad.
"Senator Hanson-Young has been a reasonable and fair-minded voice."
Mr Fraser has said that he his support for the Greens lead candidate in South Australia was for the "person, not the party".
He has said his decision to back Ms Hanson-Young stemmed from his fears that the opposition could take control of both houses of parliament and he was concerned over the "wretched" state of debate in Canberra on asylum seeker and refugee issues.
Senator Hanson-Young said voters from both sides had been disappointed by the major parties and "their desperate race to the bottom on refugees".
