MMP should be ditched to prevent small players from being king-makers in post-election negotiations, lobby group Vote for Change said yesterday.
The group endorses supplementary member (SM) as a middle ground between the current mixed member proportional and the old first past the post systems.
Under SM, there would be 90 MPs elected by winning the most votes in their electorates, and 30 list MPs proportionately based on the spread of the party vote.
Single parties would be likely to govern, instead of coalition governments.
Under FPP, all MPs were electorate-based; under MMP the total number of MPs each party gets is based on the party vote.
At the November 26 election, voters will be asked if they want to keep MMP, and which of four alternative systems - SM, FPP, preferential voting and single transferable vote - they would choose if MMP was ditched.
If a majority of voters want to keep MMP, it will be reviewed. If a majority want to change it, then a second referendum will be held in 2014 between MMP and the most popular alternative.
Vote for Change spokesman Jordan Williams yesterday tried to frame the debate around New Zealand First leader Winston Peters holding all the leverage in post-election negotiations in 1996, when he became Treasurer and Deputy Prime Minister, and 2005, when he became Minister of Foreign Affairs. "SM is a compromise between the two extremes of our current system and FPP," Mr Williams said.
"We'd still have list MPs, but fewer of them, which means the small parties still get into Parliament, but it's less likely that they'll hold the balance of power."
Mr Williams challenged Mr Peters to a debate on Sky News about the merits of a system where he could potentially be the king-maker in post-election negotiations.
Mr Peters said he had no interest in having a debate with a "jacked-up, big business-financed little cabal who want to have a political system that rewards privilege and the elite against the mass majority's interest".
The Keep MMP group was also launched at the weekend in Auckland. Keep MMP spokesman Philip Temple said SM was "first past the post in disguise, and would see us return to the bad old days of unaccountable one-party rule".SEE ALSOSupplementary member system analysed - Opinion, A11By Derek Cheng Email Derek