SAME-SEX marriage approval could happen in the next Parliament if both major parties offer a conscience vote, marriage equality advocate Rodney Croome has said.
Prime Minister Kevin Rudd said in Sunday's election debate that legislation would be introduced to federal Parliament within the first 100 days if he was returned to government.
Mr Rudd said Labor members had a conscience vote on the issue and urged the Liberal Party to follow suit. Religious leaders have condemned Mr Rudd's commitment and said it would cost him votes.
Opposition Leader Tony Abbott said the Liberal Party did not have a conscious vote on marriage equality and the decision to grant one would be made by the party room.
Mr Abbott said marriage equality was ``a very important issue'' but not a priority for him. However, that would not prevent another private members bill coming forward.
Mr Croome said Mr Abbott's response was a ``softening of his traditional opposition from the past,'' and could make supporters of marriage equality ``hopeful''.
He said the numbers on marriage equality would be ``very close'' if all parties granted a conscience vote.
``A Coalition conscience vote would give marriage equality a fighting chance,'' he said.
Three Tasmanian politicians - Braddon Labor MHR Sid Sidebottom, Franklin Labor MHR Julie Collins and Denison independent MHR Andrew Wilkie, who co-sponsored the bill - supported recently defeated marriage equality legislation.
The Senate has not taken a vote on marriage equality but five Tasmanian senators - the Greens' Christine Milne and Peter Whish-Wilson and Labor's Lin Thorpe, Carol Brown and Anne Urquhart - supported defeated legislation to have same-sex marriages conducted overseas recognised in Australia.