Opposition MPs have again failed to convince those supporting the SkyCity convention centre bill to switch sides.
The New Zealand International Convention Centre Bill narrowly passed its second reading by 61 votes to 59 with the support of United Future and the ACT Party.
The legislation will grant SkyCity a range of gambling concessions in exchange for building and operating a convention centre in Auckland.
Economic Development Minister Steven Joyce told Parliament the deal will provide jobs and growth for New Zealanders.
But Labour MP Trevor Mallard said it will lead to more harmful gambling and as a result more family breakdowns, suicides, and murders.
Green Party co-leader Metiria Turei singled out Government MPs and pleaded with them to vote with their conscience.
The legislation is expected to have its third and final reading later this month.