Voters are likely to be given at least three alternatives to MMP when they get a fresh say on the electoral system - at a cost of $23 million.
But any change will not be implemented till 2017 as National adopts a cautious, two-stage approach to its promise to hold a referendum on MMP by the next election.
The Government is also planning a $6 million advertising blitz ahead of each referendum to ensure voters are informed of the options on offer.
Under proposals unveiled by Justice Minister Simon Power yesterday, the first referendum will be held at the 2011 election and will ask two questions: whether MMP should be kept and, if not, what should replace it.
If there is majority support for scrapping MMP, it will go head-to-head with the most popular choice for replacement at a second referendum at the 2014 election.
Mr Power said options for the other voting systems to be included in the first ballot were yet to be decided, but Cabinet papers show at least three are likely.
They are first-past-the-post, which was scrapped in a 1993 referendum; supplementary member, which is a diluted proportional system; and single transferable vote, in which voters rank candidates in order of preference.
Preferential voting, which was one of the options in a 1992 referendum that led to the runoff between MMP and FPP the next year, is not included, though Mr Power said a final decision was yet to be made.
"You'd probably expect to see a familiarity about the systems that are available [as options], but I'm not counting anything in or out at the moment."
An independent panel would be appointed to run the education campaigns on all the options.
Each referendum is expected to cost $11.5m, including the advertising campaigns.
Prime Minister John Key said he believed MMP was working well and most voters did not want a return to FPP.
He has previously said he favours the supplementary system, which is similar to MMP but with fewer list members.
But Greens co-leader Metiria Turei said there was no need for a referendum.
"There's no demand for it. The MMP system is fairer for everyone. We have a democracy that's designed around representation. That is what the public want protected."
The Greens have the most to lose if MMP is dumped, as they are the only party in Parliament with list-only MPs.
ACT could also stand to lose its four list MPs, but party leader Rodney Hide said he would be happy to see MMP dumped.
Labour MP David Parker welcomed the referendum, but said it should include reforming MMP itself as one of the options.
HAVING A SAY
The Government will hold a two-stage process on electoral options.
Stage one is a referendum at the next election. This will ask two questions. The first will be whether MMP should be retained. The second will ask voters to choose what system should replace it, listing options.
If more than 50 per cent opt for MMP to be dumped, a second referendum at the 2014 election will offer a choice between MMP and whichever alternative got most support in 2011.
It would not be guaranteed that the alternative would win because, for example, some voters who voted against MMP in favour of another system in 2011 might return to it if the other option is first past the post.
If voters opt to change systems, the replacement will be used from the 2017 general election on.
- The Dominion Post
Would you pay $2 to use Auckland's motorways?Related story: Auckland motorway toll could top $350 a year