Former Minister for Justice Alan Shatter believes that "the majority of people in Ireland will support the equality marriage proposal".
"We are a very mature country now. We now have an Ireland where individuals recognise that feel that they don't have to hide the fact that they are gay, feel they can live a more open life," he told The Pat Kenny Show this morning.
"The reality is that we've had civil partnership since 2010. The ceremony to celebrate this is practically identical to a heterosexual marriage. The difference is constitutional reasons. It seems to gay individuals as a sort of second class marriage."
Speaking about the surrogacy argument that has been raised by 'No' campaigners in recent weeks, Mr Shatter said that "we shouldn't produce issues that diverge from the core of the debate".
"Much of what is being said on the 'No' side lacks social insight and sensitivity. There's commentary being made that is hugely hurtful to single parent families," he told the Newstalk radio show.
When asked about the effect that a 'Yes' outcome in the marriage referendum on May 22 would have on "family", Mr Shatter responded that "children have been fostered out to gay couples since 1952".
"When is comes to the upbringing of children that's about the individual's capacity to love children, to look after them, to develop relationships with them.
Gay people have been entitled under our laws to adopt people and that hasn't been of any major controversy. A lot of these issues are red herrings," he added.
However, Mr Shatter said that "the perception and understanding of people's individuality has changed to an extraoridinary degree in this country".
"Social evolves and we have a greater understanding of different relationships. The marriage referendum is bringing today's values and understanding of other people's relationships," he said.