With speculation the prime minister will declare her support for a conscience vote on same-s-x marriage ahead of Labor’s December national conference, a new poll suggests the issue could enable Labor to attract support from Greens voters.

Sources close to the PM have long hinted that there’d be a shift by Julia Gillard on the issue either before or at the conference, although not all the way in favour of same-s-x unions. These have been strengthened by reports in News Ltd papers today that the PM is preparing to back a conscience vote, a compromise tactic designed to head off a damaging fight over the issue between social progressives and conservatives while shifting Labor to a more liberal stance than its current “man and woman” policy.