The ‘Yes’ campaign is being urged to consider a dramatic pivot – including a “rational scare campaign” – amid a string of polls showing opponents of same-sex marriage are gaining ground.

As Monday’s Newspoll showed another drop in support for a change to Australia’s marriage laws, veteran gay rights campaigner Rodney Croome told The New Daily the ‘Yes’ campaign needed to “shift gears”.

“We need to do more to dispel some of the myths and misconceptions that are flooding our airways,” Mr Croome said.

“And we need to run our own ‘rational scare campaign’ pointing out the very real damage that will be caused by a ‘No’ vote: damage to young LGBTI people, to the families of LGBTI people, to the institution of marriage, to Australia’s international reputation and to the global marriage equality movement.”

Mr Croome, now a spokesman for the gay rights advocacy group just.equal, was “alarmed by the increasing number of people” he had encountered who had backed ‘Yes’ but “who now say they are voting ‘No’, or just not voting”.

Prominent ‘No’ campaigners, including Tony Abbott and the Australian Christian Lobby’s Lyle Shelton, have linked same-sex marriage to sex education in schools, freedom of speech and religious freedom.

‘No’ campaigners have also received significantly more media coverage throughout the campaign, according to analysis from at least two companies.

Long-time LGBTI rights campaign Rodney Croome says the ‘Yes’ campaign needs to “shift gears”. Photo: AAP

But the Equality Campaign and high-profile ‘Yes’-backing politicians have mostly chosen not to engage with the Coalition For Marriage’s attempts to widen the debate to other issues.

Instead, they have focused on positive themes of love and equality.

Mr Croome’s fear is that the ‘No’ campaign’s talking points have “hit home” with soft ‘Yes’ voters, in part, because they have been left unchallenged.

“The current campaign has done a very good job ensuring strong ‘Yes’ supporters return their ballot,” he said.

“But a pivot is required to encourage soft ‘Yes’ voters to return their ballots and that must include dispelling any doubts sown by the ‘No’ case.”

Mr Croome, the founder and former national director of the Australian Marriage Equality group, first shared his concerns in a piece co-written with the former Tasmanian Anti-Discrimination commissioner Robin Banks for youth pop culture website Junkee.

That piece was designed at giving “voice to a growing concern in the grassroots marriage equality movement” to “persuade the ‘Yes’ campaign to shift gears”, he told The New Daily.

‘Yes’ support declining

Mr Croome and Ms Banks say those who have switched their vote to ‘No’ or no longer plan to vote have almost universally cited “the No case’s talking points about freedom, school curricula, and to a lesser extent who should raise children”.

“The arguments are out there and we need to address them or risk looking like we are trying to hide something,” they wrote.

Monday’s Newspoll showed support for same-sex marriage had fallen to 57 per cent, down from 63 per cent in August. It was the latest in a series of surveys showing a gradual erosion of support for the ‘Yes’ side.

That poll comes as an unsolicited national ‘Yes’ text message blast stirs a backlash among some voters and with ‘No’ campaigners seizing on last week’s alleged attack on Tony Abbott in Hobart.

Mr Croome said the ‘No’ campaign’s plan was “basically a voter suppression campaign, made much easier by the fact this vote is not compulsory”.

“The obsession of the anti-equality movement with having a public vote at all costs is because they believe they can scare enough soft ‘Yes’ voters into voting ‘No’, or not voting, through their over-the-top fear-mongering, that they significantly erode the ‘Yes’ vote,” he said.