There are still a few weeks left to run in the same-sex marriage postal ballot campaign, and millions of votes are yet to be returned – or not returned.

With 67.5% of ballots now in, Equality Campaign executive director Tiernan Brady says the high turnout shows the importance of a “yes” vote to people’s lives and dignity.

He says tyranny of distance in Australia has made campaigning difficult, compared to his experience during Ireland’s marriage referendum.

Despite criticism of what some saw as invasive tactics, Brady describes the efforts made by the “yes” campaign as largely positive and respectful. However, he admits there have been unfortunate incidents and “clowns” on both sides, but that they were largely “on the fringe”.

On the “no” side, Australian Conservatives senator Cory Bernardi is unwilling to concede defeat. He praises the “grassroots movement” and “rockstar” mums and dads.

On the Abbott factor, he says high-profile “no” voters have been “very effective”.

If the “yes” vote wins, Bernardi foresees a few contentious debates over protections for religious freedoms and freedom of speech. “If the government is serious … they won’t embrace the [Liberal senator Dean] Smith bill.”

Bernardi’s party has benefited somewhat from the same-sex marriage debate: he estimates his party now has the third-largest membership in Australia.

Michelle Grattan does not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and has disclosed no relevant affiliations beyond their academic appointment.