For starters, to actually govern they would have to win half the seats, not just one. As they transition from a minor party to a major player they would have to undergo some fundamental changes. They would have to have an increased focus on their ability to manage well rather than focussing on ideology. This would be more of a pre-requisite than a result of gaining power. I personally don't see it happening, as the parties carve out niches for themselves and attract appropriate candidates. The minor parties will always attract the ideologues and the major parties the managers. It would only happen if one of the major parties imploded somehow, then a minor party would rise to fill the vaccuum and in doing so change itself.

Its actually interesting to look at our basically 2 party system, which we have in common with the US and UK, and compare it to the systems of other countries including some European countries where no party is able to form government in its own right, and there are often changing co-alitions (and changing governments). I dont know heaps about that alternative political environment, but is anyone in the position to comment on whether this detracts from or adds to (or is simply no different) political, domestic and economic stability?

I think that you tend to get more, smaller parties when you have multi member electorates (ie proportional representation).

Having shifting coalitions can create political instability (eg Israel) but I'm not sure whether this tends to translate into policy instability. The US government suffers from instability that results from using first past the post voting, which tends to widen the ideological gap between the two major parties. Compared to this, Australia's government is extremely stable, with both major parties being very similar ideologically.

http://www.ozpolitic.com/electoral-reform/electoral-reform.html

Actually, the answer to both FH and CG is 'proportional representation' - like we have in the Senate, in a modified form in Tasmania and they do in some European countries. Our system, under which the winner (i.e. that candidate who can, by hook or by crook, secure 50% +1 of the vote) takes all, is hopelessly undemocratic and results in the stupid system where power alternates between two major political parties who look more and more like each other. This is exacerbated by compulsory preferential voting.

I don't think that the Greens seriously contemplate governing in their own right in the forseeable future, but they do contemplate participating in government. That is why they have a comprehensive range of policies that covers every politically salient issue and portfolio.

It is not undemocratic. It is just a different level of representation - more local. having two similar major parties because of compulsory voting is far better than having government switch between wildly differing extremist parties.

My favoured option is voting by delgable proxy. It would largely do away with parties, but maintain stability. It would bring us closer to direct democracy, but only for those who want it.

http://www.ozpolitic.com/electoral-reform/electoral-reform.html#direct-democracy

“Are you intending to vote informally in the Senate as well as the House of Reps?”

Unfortunately yes CJ.

In the senate we either mark one square above the line or every square below the line.

If we mark one square above, preferences end up counting for one of the two major candidates in manner that is predetermined and completely out of the control of the voter.

If you vote below the line you have to mark every square, so no matter how you mark them your vote will filter down until it counts for one of the two front-running candidates.

So as with the lower house, the voter effectively does not have the choice to vote against both major candidates.