The Greens may have successfully lobbied Speaker David Carter for a conscience vote on the International Convention Centre Bill.
But in the end the vote held little drama, with all National MPs heeding Prime Minister John Key's call to support the legislation.
ACT leader John Banks and independent MP Peter Dunne also voted for the bill, ensuring it passed its first reading 61 to 59 in a vote that was strictly along party lines.
The legislation will facilitate a deal for for SkyCity to design, build and run a $402 million convention centre that proponents say will draw 20,000 to 30,000 extra business travellers a year.
In return, the casino operator will gain 230 new pokies, cashless gaming and an extension of its gaming licence (due to expire in 2021) until 2048.
The bill had been expected to pass. SkyCity shares [NZX:SKC] closed unchanged at $4.38, close to the top of its 52-week range ($4.58/ $3.41).