An upcoming referendum on same-sex marriage could result in a landslide victory for marriage equality, a poll has found.

An Irish Times/Ipsos Mori poll was carried out on the issue this week, ahead of a planned referendum on same-sex marriage which is scheduled for May 2015.

When quizzed on voting intentions, 67 percent of people said they would vote for equal marriage, 20 percent said they would vote against, 3 percent refused to answer, and the rest were undecided.

With undecided voters excluded, a huge 77 percent of people polled will back equal marriage next year, with just 23 percent voting against.

However, despite the good news for the equal marriage lobby, referendums in Ireland have a history of surprise upsets, due to their frequency, low turnout, and powerful religious lobbying groups.

The exact date for the referendum is still yet to be announced – though the Irish Cabinet confirmed earlier this week that it is expected to take place in May 2015.

It was previously expected to take place in Autumn 2014, but eventually slid to ‘early 2015’ amid uncertainty.

Northern Ireland currently has no plans to introduce same-sex marriage.