A Facebook page has been created in the hope of making Rotorua MP Todd McClay vote in favour of same-sex marriage.
Mr McClay voted against the Marriage (Definition of Marriage) Amendment Bill on Wednesday night. The bill would allow for same sex marriage.
Waiariki MP Te Ururoa Flavell voted for it.
The bill's sponsor, Labour MP Louisa Wall, told Parliament and a near-full public gallery that the discussion of her bill had highlighted the discrimination felt by gay communities in New Zealand.
MPs voted to support the bill by 77 votes to 44.
The Facebook page called Todd, vote yes for marriage equality, was set up on Thursday and had attracted more than 50 likes. The page is encouraging people to contact Mr McClay and share their views about same-sex marriage.