New Zealand’s Parliament is on Wednesday expected to give final approval to a bill which would legalise equal marriage in the country.

In its third reading on Wednesday evening, the equal marriage bill, introduced by MP Louisa Wall, is expected to pass, which could see same-sex weddings taking place from mid-August onwards.

Back in March, MPs voted 77 to 44 in favour of the bill, allowing it to pass to this third and final vote.

The select committee heard from 2,900 unique lobbies on either side of the debate during its consideration period.

Green MP Kevin Hague, said he had seen a large increase in support from within the LGBT community, as well as from straight supporters.

“I just feel enormously grateful to them because they have no personal stake in it, they just say this is the right thing to do,” he said.

“After this bill passes we will effectively have equality under the law, which is one of the basic human rights,” continued Hague.

Both the the Conservative Party and lobby group Family First, have been running campaigns against the bill.

The issue will be a conscience vote, which means MPs are free to make up their own minds, rather than adhering to party lines.

Bob McCoskrie of Family First has been running a campaign to ask supporters to sign a “marriage pledge”, saying they will not vote for any MP or political party in support of Louisa Wall’s bill.

“The definition of marriage should stay as traditionally and commonly conceived – not one manipulated by politics and political correctness,” he said.

Minor changes had been made since the bill’s first vote in August, which passed overwhelmingly in favour, 80 votes to 40.

Clarification has been added that churches would not be forced to perform weddings for same-sex couples, and this was backed up by the Human Rights Commission.

Large crowds are expected in the public galleries for Wednesday’s vote, including several celebrities.

If it passes, New Zealand would become the second Commonwealth realm, with Elizabeth II as its reigning constitutional monarch, to legalise equal marriage, as Canada legalised equal marriage in 2005.

The country would become the third of the 54 Commonwealth member states to allow legislation for marriage equality, as South Africa legalised same-sex marriage back in 2006.

A recent poll commissioned by Family First found that more people support the idea than oppose it, however another study found that opposition to equal marriage had risen, with 48% now polling against – up from 40.5% last June.