voting system would be held alongside the 2011 general election. Enabling legislation The Electoral Referendum Bill to legislate the referendum was introduced to Parliament on 25 March 2010, and passed all three readings unanimously. The bill received its Royal Assent and became the Electoral Referendum Act 2010 (Public Act 2010 No 139) on 20 December 2010. In the original version of the bill, there was no advertising spending limits. At the Select Committee stage, a $12,000 spending limit for unregistered promoters and a $300,000 spending limit for registered promoters was added in response to public consultation to "level the playing field", to "protect the integrity" of what is a constitutionally significant referendum, and to prevent wealthy individuals from influencing the outcome. This largely came from the original 1993 referendum legislation not having spending limits, allowing the anti-MMP Campaign for Better Government (CBG), which was backed by a large business lobby, to spend an estimated $1.5 million in advertising compared to the pro-MMP Electoral Reform Coalition's $300,000. The limits were also designed to match the new spending limits by third parties in general elections, which were introduced by the Electoral (Finance Reform and Advance Voting) Amendment Act 2010 that commenced at the same time as the Electoral Referendum Act on 1 January 2011. Other amendments were proposed at Select Committee and Committee of the House but were not passed. The ACT Party proposed including a third question on whether to retain or remove the separate Maori seats (rejected due to a clause in the confidence and supply agreement between the National and Maori parties) and to increase the registered promoter spending limit to $500,000 or $750,000. The Labour and Green parties proposed holding the review of the MMP system regardless of the referendum results. Referendum When voting in the 2011 general election, voters received a purple referendum ballot paper in addition to their normal orange voting paper. The ballot paper asks two questions. Voters could choose to answer both questions, only one of the questions, or neither question. Once the voters made their choice, the referendum ballot paper was deposited in a separate purple-coloured ballot box under their respective electorates. The first question is "Should New Zealand keep the Mixed Member Proportional (MMP) voting system?" The options provided are: I vote to keep the MMP voting system I vote to change to another voting system Simple Yes or No answers to