DUBLIN: Ireland could become the first country in the world to vote for same-sex marriage in a historic referendum this week in this traditionally Catholic nation.
Voters on Friday will be asked whether or not to add an article to the Irish constitution saying: "Marriage may be contracted in accordance with law by two persons without distinction as to their sex."
The latest polls show the "Yes" side in the lead. Volunteers for and against gay marriage have been canvassing door to door in recent weeks and billboards have appeared appealing for votes, as a colourful "Yes" bus makes its way around the country.
All the main political parties, including conservatives, are supporting the change , a seismic shift in a country where homosexuality was only decriminalised in 1993 and abortion is still illegal.
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But a "Yes" victory is by no means certain and there is concern among proponents about whether "Yes" supporters will come out and cast their ballots.
"We will ensure that people will be treated equally, no matter who they love," Prime Minister Enda Kenny has said.
The move is opposed by the Catholic Church, whose influence has waned in Ireland amid growing secularisation and after a wave of child sex abuse scandals that badly discredited the hierarchy.
"Marriage should be reserved for the unique and complementary relationship between a woman and a man from which the generation and upbringing of children is uniquely possible," the Irish Catholic Bishops' Conference said in a statement.
An Irish Times/Ipsos MRBI poll published on Saturday showed 70 percent support for the "Yes" side and 30 percent for the "No". The same pollsters in March had given the "Yes" side 78 percent.
There is a clear divide in the polls, with many older people and rural residents intending to vote "No".
Eighteen countries around the world have so far legalised gay marriage or are about to do so, including 13 in Europe. Across the border in Northern Ireland, gay marriage is banned even though it is legal in the rest of Britain.
Referendums have previously been held in Croatia and Slovenia, and in both cases voters rejected legalising gay marriage. In Slovenia same-sex marriages were, however, legalised by parliament in March.
The constitutional referendum in Ireland would have to be followed by specific legislation passed in parliament.
While the country has undergone vast economic and social change in recent decades, abortion is still banned except in cases where the life of the mother is in danger. Thousands of Irish women seek abortions in Britain every year.
The central "No" argument is that the constitutional amendment would undermine the traditional definition of marriage and would facilitate laws allowing gay couples to adopt or have surrogate children.
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"Children are the real issue," Margaret Hickey, a spokeswoman for one of the leading "No" groups, Mothers and Fathers Matter, told AFP.
"I think it's important to defend the right of a child to a mother and to a father at least at the start of their lives," she said.
But officials have pointed out that same-sex couples can already adopt children under the current legislation.
The debate has become increasingly heated, with the "No" campaign saying they have been vilified and some of their posters have been defaced.
The "Yes" side has been boosted by the support of sports, music and film stars including Irish Hollywood A-lister Colin Farrell and U2 frontman Bono.
"Trying to co-opt the word marriage is like trying to co-opt the word love," Bono was quoted by the Irish Times as saying ahead of the start of his world tour in Canada last week.
In a YouTube video supporting the change, comedy TV star Mrs. Brown -- a man dressed as an old woman -- likened the furore to controversy in the past over marriages between Catholics and Protestants and between black and white people.
"They still went and got married and the world didn't end and we all grew up a little bit," she said in her "message from the mammy-in-chief".
Jerry Buttimer, a lawmaker with Kenny's Fine Gael party and one of the few openly gay politicians in Ireland, said it was about making Ireland a more equal nation.
"As a country we have come on a journey," he told AFP.
Amnesty International Ireland chief executive Colm O'Gorman said it would be a "phenomenal message for Ireland to send to the rest of the world."