"You only have to look no further than Daniel Andrews, the Premier of Victoria, one of the country's most vocal supporters for changing the definition of marriage," Shelton said.



"He is about to make [LGBTI anti-bullying program] Safe Schools compulsory in all Victorian high schools next year, allowing boys who identify as girls to be in the girls' toilets and all of this fluid gender ideology material," Shelton said.

Brady told BuzzFeed News such comments show the "no" campaign has "literally given up on trying to win the argument about marriage".

"The game is over. They know Australians are for it – 'so how can we make it about something else?'" he said.

"You can deliberately try and fool people. They’re hoping that by the time we can make clear how untrue and how unconnected it is, we’ll be on the far side of the decision. As a tactic, it is one you have to work very hard to defeat."

Paul Ritchie, Tony Abbott's former speechwriter, told The Drum that pivoting the argument against same-sex marriage towards parenting or transgender people is "an old political trick".