The Act Party has taken a desperate step by declaring at this early stage that it will give National another confidence and supply agreement after the election. This is the first time the party has committed itself to such an agreement before the ballot rather than waiting to see what it might do with the votes it receives. It is a decision Act will not have taken lightly.
It weakens the party's ability to bargain for any particular policies or cabinet positions after the election, as leader Don Brash concedes. The decision was made, he says, to give voters an assurance of stability. Act wants to give them no reason to fear it would cause any complications for National in a second term.
Clearly the party has discovered that very few of its possible voters want it to be the force that Dr Brash implied it might be when he took over the leadership a few months ago. Its position in polls has not improved since the takeover. The party's only prospect of survival remains the Epsom electorate where it has replaced one of its founders with a National Party veteran.
The pre-election commitment is an admission that Act's only purpose now is to support National. It has been reduced to the same role that Jim Anderton's Progressive Party has performed for Labour. MMP allows a safe seat for National or Labour to be worth two or more votes in Parliament if the seat is given to a loyal supporting party. Mr Anderton, long after he was reconciled with Labour, maintained the fiction of an independent party for just this purpose.
In latter years he could not win enough nationwide votes to give Labour additional seats but continued to enjoyed a foothold on the national stage, taking part in television leaders' debates though he represented nothing more than any other electorate MP.
Winston Peters long prospered on a single electorate too, as has Peter Dunne. As a centrist "party" of one, Mr Dunne has been able to bargain for a place in successive National and Labour governments and must be setting a New Zealand record for continuity in office.
John Banks could enjoy a similar role if he wins Epsom for Act, though Dr Brash would claim a leader's place on the stage if Act's nationwide vote is enough to bring him in too. He has, though, ruled himself out of a senior Cabinet post by observing in the Herald last week that there was "no way" Mr Peters had a mandate to be made Treasurer in 1996 or Foreign Minister in 2005.
Dr Brash and Mr Banks have evidently asked National for nothing more than a clear run at the Epsom seat, which National has granted by selecting a candidate who says he will concentrate on the party vote. But they are asking a lot of voters' tactical awareness when they offer them no reason to vote Act except to keep National in office.
Rodney Hide offered them something more. He was a novelty for Epsom at the last election, a cheerful figure who courted them in a canary yellow jacket. He became less attractive as a minister and was considered certain to lose the seat. Mr Banks is already well known, but as a defeated mayor seeking a second life in Parliament, he is unlikely to excite the electorate.
By promising National support on votes of confidence and money supply, and asking nothing in return, Dr Brash and Mr Banks have diminished a party that has stood for much more. It has been hard for any small party to survive when its senior partner is governing and popular. Act was always in danger of going the way of New Zealand First, the Alliance and possibly now the Maori Party too.
Dr Brash took over Act not to save it but to keep National in power. To that end he has removed Act's last shred of independence, given away its influence and reduced it to a shadow of the party he really serves.