Former prime minister Tony Abbott's daughter has taken centre stage in the marriage equality campaign, as the Catholic archbishop of Brisbane compares same-sex marriage to parents wedding their own children.
The high-profile interventions come as two national polls paint different trends of attitudes towards same-sex marriage.
An Essential poll published on Tuesday shows 58 per cent of Australians want the law changed to allow same-sex couples to marry, up three points from a week ago.
Opposition has dropped slightly to 33 per cent while nine per cent is undecided.
However, Newspoll figures released on Monday pegged support for same-sex marriage at 57 per cent, lower than the 63 per cent in August and 62 per cent in September last year.
One person who has made up their mind is Frances Abbott, who features in a new 'Vote Yes' campaign video in which she says marriage equality will make society less lonely for many people.
"I think it's well known that within my family we have people that sit on the other side of the fence," Ms Abbott says in the clip.
"My mother and my father raised me to stand up for what I believe in."
Her father has campaigned heavily against same-sex marriage.
Mr Abbott was headbutted in Hobart last week and linked the assault to violence from 'yes' campaigners.
However, his attacker who was wearing a 'yes' sticker, rejected the link, insisting the incident was fuelled by personal hatred.
In the video, Ms Abbott talks about her aunt Christine Forster and how she hopes to be part of her same-sex wedding one day.
Ms Foster, a Liberal councillor for the City of Sydney, is campaigning against her brother on the issue.
Some 36 per cent of those polled by Essential already voted in the postal survey (more than double the number in Monday's Newspoll results), while 45 per cent say they definitely will and eight per cent say they probably will.
Of those who have already voted, 72 per cent support same-sex marriage and 28 per cent oppose.
Those who are yet to take part but say they definitely will are more likely than average to vote 'no'.
Meanwhile, Brisbane's Catholic archbishop, Mark Coleridge, has cited society's refusal to accept the marriage of parents to their children in urging Australians to vote no to same-sex marriage.
Archbishop Coleridge says while the love of same-sex couples must be respected, society has always discriminated about who can marry.
"I mean parents can't marry their children. Children can't marry their parents. Sibling marrying sibling has always been ruled out," he said in comments broadcast on ABC radio.
Earlier this month, Archbishop Coleridge wrote that only the love of a man and a woman was nuptial.
He said all human beings were equal "but that doesn't mean they are the same".
"Same-sex marriage ideology implies that equality means sameness. But it doesn't."
Three-quarters of those who do not support same-sex marriage are worried about religious freedoms, the Essential poll found.
However, 58 per cent of respondents were not concerned.
