Former prime minister Bob Hawke has savaged the same-sex marriage postal survey as the worst economic decision by any prime minister since federation.
Mr Hawke interrupted a Q&A session with former Labor foreign minister Gareth Evans at the National Press Club to lament the fact the survey could not produce a decision.
"It still requires a vote of the parliament, whatever the result of the vote is," he said in Canberra on Wednesday.
"It costs 122 million bloody dollars. Can you imagine a prime minister would make a decision in these stringent times, spending $122 million on a process that can't produce the result?"
Mr Hawke said the money would be better spent bridging disadvantage among indigenous Australians or on education.
"Without any question the worst economic decision made by any Australian prime minister," he said.
Another ex-prime minister, Tony Abbott told Sydney radio station 2GB Mr Hawke is suffering from memory loss, pointing to the Gillard government's costly school halls program as a poor economic decision.
Mr Evans said while prime minister Malcolm Turnbull's instincts were "decent and civilised" he had "sold himself completely to the trogs (troglodytes) in his party" on both marriage and energy policy.
He said it was "screamingly obvious" the Australian community wanted same-sex marriage legalised.
New polling figures paint a promising picture for supporters of same-sex marriage.
Essential polling released on Wednesday showed 61 per cent of people believed same-sex couples should be able to marry, while 32 per cent thought they should not.
It found 64 per cent of respondents who had already returned their ballots voted 'yes' and 30 per cent voted 'no', while half of those yet to complete their survey plan to vote 'yes' and 36 per cent are voting 'no'.
The Australian Bureau of Statistics received roughly 9.2 million ballots, or 57.5 per cent of the forms it sent out, by the end of last week.
Mr Turnbull believes the estimate shows Australians wanted to have their say after Labor blocked a promised plebiscite which would have been held in February.
"I think it is a ringing endorsement of the government's decision to give every Australian their say on this issue," he told ABC radio on Wednesday.
Mr Turnbull expects the very high participation rate to increase with more than four weeks to go before the ballot closes.
Labor leader Bill Shorten still insists the $122 million cost of the survey could have been better spent, but is pleased with the turnout.
The postal survey closes on November 7, with the results to be published on November 15.
