Indeed, all evidence suggests that most people made up their minds long before they received any ballot papers. The factor most likely to sway the result is the size of the turnout, with most observers expecting that, the higher the turnout, the more likely that "yes" will win.

The second, associated, factor is the degree that younger Australians take part. Polls show that the younger the average age of voters taking part, the more likely that "yes" will win.

At most elections, in nations with voluntary voting, younger voters are usually less likely to be enrolled, less likely to be emotionally or intellectually engaged about the issue in context, and more likely to be cynical about the power of their choice to affect the outcome. Even if mildly enthused about the issue, they are often less likely to plan the process of voting effectively, if only because they are less in a habit of doing so.

Yet, if the tempo of what has passed for debate is any guide, the "yes" campaign looks as if it is has been rather more successful in making its cause a campaign, and a matter upon which one should take a stand on principle. The "no" campaign has been largely predictable, with little evidence of having aroused great enthusiasm among constituencies where it needs to win. Heightened efforts by "no" organisers to arouse their own side may primarily serve to get lazy "yes" voters to go and post already-filled-in ballots left lying around.

Many religious leaders have been sincere but entirely predictable in arguing for "no". Perhaps some of their followers will vote en masse in support of what they say, either because they entirely agree or because they are used to following the advice of senior officials.

But it has been a long time since any religious leaders in Australia had a strong influence over their followers' social or political choices. From the 1970s, for example, Australian Catholic women were as likely as any other Australian women to be using oral contraception and as likely to have had an abortion. This was in spite of unambiguous declarations of the intrinsic sinfulness of both from their church, and, if not always from their priests, from their bishops and archbishops.

There is little evidence these days of blocs of voters able to be swayed, on account of some church demand for loyalty, towards one party of another. Put bluntly, "guidance" from many of Australia's church leaders does not command enormous respect in the marketplace of ideas or, increasingly, ideals.

This is not only a function of the growing secularisation of society, of declining attendance at religious services, or a reduced role for religious leaders in public and political forums. It is also a function of squandered moral authority, because of scandals such as the response of church officials to high levels of physical and sexual abuse of children and other vulnerable people. These raised serious questions about the stewardship, governance and management of most of Australia's religious institutions.

Other who might once have listened carefully are now increasingly inattentive as they have seen some church leaders seem to be obsessed with issues of personal sexual morality (including attitudes to homosexuality) while seemingly much less concerned with wider moral and ethical issues.

But the problem that "no" organisers face is more than one of the relatively low status and moral clout of some religious leaders. It is also the way in which division within religious organisations has made it clear that even hard-line churches are not monolithic on the question. When they are not, it is harder to say that fundamental principles are involved.

Several Catholic bishops, and a number of other influential religious leaders, have made it clear that Catholics can, in good conscience, vote for civil recognition of same-sex marriage. They have reinforced the view, held by most Catholics anyway, that it is neither a moral nor a religious issue.

This is a big, and intentional, slap in the face for most senior bishops, who have argued that their absolutist view is self-evidently true, stems from natural law and represents a principle so fundamental and important that it must override the right of any dissenter, even of no religious belief at all, to have an alternative approach.

It seems unlikely that the "apostates" will make a decisive difference in the outcome. Their undermining of the episcopal caucus will not make them more popular in Rome, or in the archbishops' palaces.

But some of those archbishops, indeed, will have personally contributed rather more to the "yes" vote – not least with threats levied against teachers, nurses and other (state-paid) employees of Catholic service organisations if they made any public statements that undermined the party line. It hardly sits well with a key tactical part of the "no" campaign: that, somehow, a "yes" vote will undermine religious freedom and freedom of speech.

Bishops on the "no" side will argue, of course, they have no choice but to campaign strongly, even at the risk of public humiliation or repudiation. Church teaching cannot be determined by opinion poll, they would say.

Yet it may be that a core part of the problem is the inflexibility with which they conflate a church teaching they are well entitled to believe in, and are perhaps under a duty to promote, with the civil side of the institution of marriage.

If one is to marry legally in many Catholic countries, such as Italy, one must go to a town hall and marry before witnesses in a civil ceremony presided over by a civil servant, such as a mayor.

Then, if one wants to call for the blessing of God upon the union, one can go to the church or cathedral and receive the sacrament of matrimony, perhaps in a full nuptial mass. The Catholic church in Italy will not permit a church wedding unless there has already been a civil wedding. In Italy and similar countries, the church does not claim or pretend that its ceremony creates the legal and social conditions of civil marriage. That's for the state.

In Australia, authorised religious celebrants are allowed to unite the civil and the sacramental aspects of marriage in the one ceremony.

But there is nothing in Catholic canon law, or in many nations' laws and customs, that requires the conjunction. One could adopt legislation in Australia requiring all people proposing to marry to register their civil marriage before a civil celebrant without a serious peep from the Catholic church. It may be argued against on the ground of English custom or convenience, but not as a matter of faith or morals.

Alternatively, the government could continue to license religious celebrants to perform civil marriages, but insist that there be a distinction between the civil function – with its legal and temporal incidents – and whatever was claimed of its religious or sacramental function.

In many countries that followed the British custom of permitting the two ceremonies, most people were once married, in the civil as well as the religious sense, by a religious minister. But Australians increasingly prefer marriage by a marriage celebrant anyway.

Churches recognise that, whether or not God is invoked, those who submit only to the civil ceremony are legally married.

Civil marriage was the norm, with or without sacramental matrimony, for most of the history of Christendom. In most countries, it came within the province of religion rather more because ministers – clerics or "clerks" – were usually literate, and able to put such local matters on to a record (in much the same way that their baptismal and funeral records served for many centuries as records of births and deaths). The Christian church also claimed jurisdiction over annulment and divorce, and thus had some concern for form that the state did not necessarily have.

Even so, the distinction between civil and religious marriage was always recognised, and was instanced by often unpleasant rules, such as the refusal of full religious rites, or a ceremony in a church, in the case of mixed marriages.

The history, and the distinctions, are not of mere historic interest. A tactic of those advocating a "no" vote is to raise a fear that somehow allowing same-sex civil marriage could interfere with religious or traditional freedoms. We are invited to infer that, down the (slippery) track, ministers will be required, against their consciences, to marry same-sex couples, or that they may be persecuted or prosecuted for restricting the sacrament or religious blessings of matrimony on same-sex couples.

One way or another, the government has pandered to this tactic by being silent about the "protections" it will build into its legislation for same-sex marriage.

Actually, it needs no protections at all. It could avoid this by saying, simply, that all it proposes to do is to legislate to allow same-sex civil marriages, having exactly the same temporal and legal incidents as for opposite-sex marriages. Religious ceremonies and sacraments are not the business of, or in the province of, the state. Religious organisations already have generous (some say overgenerous) exemptions for their beliefs and practices under existing anti-discrimination laws.

It would also serve to simplify invented crises of conscience – the religious baker, for example, claiming a conscientious objection to making a wedding cake for a same-sex couple. Or for that matter, the approach a religious organisation disapproving of homosexuality could adopt to refusing to employ a gay doctor in a religious hospital or a gay teacher in a church school. These situations have long been covered under existing discrimination laws, and those imagining fresh potential crises are usually simply trying to reopen arguments they lost long ago.

Strangely, the public debate has seemed to involve little reflection, by either side, on other "traditional" aspects of civil marriage.

Marriage has always involved more than the mere recording of an indefinite partnership between two people. It affects property, wider family members (new and to come), and creates an array of presumptions, obligations and rights involving legitimacy, domicile, property, mutual care and sustainment.

It was at once a personal exchange of vows between two people, and a public declaration of a new partnership to the world. The latter also gave rights and presumptions for the public as much as the couple. It once usually involved alliances between families, and adjustments of income, property and expectations that affected many more than the couple getting married. Those others had interests that needed to be borne in mind.

The modern citizen knows of the second-rate citizenship of wives in traditional marriages up to the 19th century. They were "property" passed from fathers to husbands, and without much in the way of rights, legal personality or capacity to manage assets. That may now have changed, without much in the way of support from religious organisations, but its passing should not ignore some attraction in the idea that marriage created, for some purposes, one person out of two.

Patterns of marriage have changed enormously over the centuries. Some of the sentimental ideas of what "traditional" marriage was, or was supposed to be, are simply artefacts, like white picket fences, of some imagined idealised time in the past. Typical marriages of the 1950s bore little relationship to the marriages of the 1920s or 1880s.

Even the traditionalists must understand that there is great force in some modern radical critiques of old-fashioned marriage. That extension of the right of marriage to same-sex couples has become a cause does not necessarily mean that people want to copy old models of personal relationships.

But the issues and incidents of marriage, traditional or otherwise, do not differ much according to whether it is between different sexes or the same sex. We would be better off focusing on ways of making partnerships and relationships work, more equal, and more mutually sustaining – more centripetal than centrifugal. The real crises of marriage from which we are all distracting ourselves are of keeping people together, not of keeping them apart.

Jack Waterford is a former editor of The Canberra Times. jwaterfordcanberra@gmail.com