The bill will be introduced to the House of Representatives after it passed the country’s upper house of parliament on Wednesday afternoon.

Forty-three senators voted for the Marriage Amendment (Definition and Religious Freedoms) Bill 2017, while 12 voted against it.

The moment was met with a standing ovation in the packed public and parliamentary galleries.

Senators from various parties hugged each other and cried following the vote, with some declaring it the proudest day in their parliamentary careers.

"This is the Senate's day," Liberal senator Dean Smith said shortly after. "This is a demonstration that working across the chamber ... does deliver not just good outcomes but fantastic outcomes."

Attorney-General George Brandis said he was ‘so proud of Australian democracy today, more proud than I have ever been’. It was a day to ‘rejoice in what the Australian people achieved this year’, he said.

Senator Smith, the first openly gay Liberal MP, helped drive the change within the Coalition and sponsored the final bill that passed the chamber essentially unchanged on Wednesday afternoon.

"We have seen in this debate how our Parliament is meant to work," he said. "The real question out of this debate is why isn't our Parliament like this more often?"

Parliamentarians from both sides had a conscience vote on the bill, and many chose to abstain, including Employment Minister Michaelia Cash, Assistant Social Services Minister Zed Seselja and One Nation leader Pauline Hanson.

The bill will go to the House of Representatives next week, after Prime Minister Malcolm Turnbull cancelled the house’s sitting week this week.

This story originally appeared on The Sydney Morning Herald as Same-sex marriage passes the Senate 43 to 12 in historic political moment.