On Saturday, voters will be met with a record 529 Senate candidates and 1188 House hopefuls.
While the result in the House of Representatives on Saturday now looks settled in the Coalition's favour, the final numbers in the Senate are anything but clear. The Coalition could secure a majority in its own right, or it might assemble a workable majority with assistance from right-of-centre minnow parties, or the current Labor-Greens majority might persist. One potential surprise involves Arthur Sinodinos and/or Helen Kroger - Liberal senators from NSW and Victoria respectively - forfeiting their places to Pauline Hanson and a Family First candidate. The uncertainty about the Senate result is the product of a combination of two factors: the Senate's unique electoral system, and the ease with which political parties can be registered under the Electoral Act.
Technically, senators are elected by way of a multi-member, quota-preferential, single-transferable-vote proportional system. This mouthful, which is almost as complex as it sounds, is generally abbreviated to STV. Under STV, each state is allocated 12 senators, six of whom usually face election at three-yearly intervals. The territories each have two senators, both of whom face the people at each ordinary election. In the House, a successful candidate needs an absolute majority of 50 per cent plus one vote; in the Senate, each candidate must achieve a ''quota'' of votes - 14.4 per cent at the usual half-Senate elections, such as the one this Saturday, or 7.7 per cent at the full Senate elections that follow a double dissolution of both chambers (which last occurred in 1987).
The system allows the preferences of parties and independents eliminated from the count to be distributed in the same manner as in the counting of votes for the House. The major difference, and a key feature of STV, is that the ''preferences'' of the big parties are also distributed, even after they have won some Senate positions. This works in two ways. The lead Senate candidates for Labor and the Coalition attract votes far in excess of what they need to win a place. Those surplus votes are transferred down the ticket and help elect other candidates from the same party. Since major parties rarely win exact quotas, their ''surpluses'' can also transfer on and help elect other parties' candidates.
Take the example of NSW in 2010. After all the first votes were tallied, the Coalition had 2.3 quotas, which it built to three by harvesting preferences from a clutch of small right-wing parties such as the Democratic Labour Party and the Shooters and Fishers Party.
Labor started with 2.2 quotas and was not so fortunate in reaping small-party support; rather than contributing to a third senator, its 0.2 surplus helped to elect a Greens candidate. Most small and micro-parties get elected by receiving the sugar hit of a partial quota from a big party. (The present exception is Nick Xenophon in South Australia, who will probably again win his own quota.)
It is this churning of preferences that permitted the election of candidates such as the Victorian DLP's John Madigan, who won only 2.3 per cent of the first vote.
A claimed virtue of proportional representation systems is that they allocate seats in direct proportion to votes won, so if a party wins 15 per cent of the vote it should receive 15 per cent of seats. The Senate is not quite like that because the existence of eight electorates (the states and territories) dilutes national proportionality. The system is best termed quasi-proportional.
Why did the Parliament adopt this Senate voting system in 1948? Mainly because, under the old system, a party that achieved even the narrowest majority in a state won all three Senate places. Nevertheless, the opposition leader at the time, Robert Menzies, called the change to the present system a ''racket'' designed to maintain a Labor majority until 1953. In fact, the Labor majority was swept away at the 1951 double dissolution election.
A controversial feature of the present system is the above- and below-the-line voting option. Above the line, voters cast a valid vote simply by entering the number 1 for the party of their choice; below the line, they must indicate a full set of preferences, which can mean numbering dozens of boxes. Above-the-line is a gift to party managers making preference deals of sometimes bizarre ideological inconsistency. Below-the-line raises the risk of pushing up the accidentally informal vote.
The above-the-line method was introduced by the Hawke government in 1983 to reduce the traditionally high Senate informal vote. But Labor was also keen to prevent a repeat of the 1974 election, when anti-Labor interests packed the NSW Senate ballot paper with dummy candidates and caused a spike in informal votes. The ruse cost Labor a quota, with devastating consequences for the party in 1975.
On Saturday, voters will be met with a record 529 Senate candidates and 1188 House hopefuls. An unprecedented number of recently created micro-parties will also participate. Some may view this as a sign of a healthy democracy, but they would be wrong. At least in NSW, the huge number of tiny right-wing parties running for the Senate is the result of the efforts of a political deal-maker who specialises in constructing mutual preference arrangements in order to increase the chance of a victory by someone who enjoys minimal direct support.
The number of parties and candidates contesting House seats has also leapt. This will inflate the informal vote, especially in areas where people whose first language is not English are concentrated. Mostly, these are Labor-held seats.
Reform is needed. First, the test for party registration should be much stricter. At the moment, all a ''party'' needs is $500, a brief constitution and a list of 500 supporters entitled to be on the electoral roll. This should be increased to 2000 voters and a $20,000 nomination fee (or $10 a member - just over half the cost of a packet of cigarettes).
Second, the Senate ballot paper should be redesigned to abolish above- and below-the-line voting. Instead, voting should be optional preferential. At a normal Senate election, a voter would need to number at least six squares, and at a double dissolution election at least 12. This would keep informal voting low and put a stop to secret wheeling and dealing over preferences and unexpected successes for candidates with extremely modest direct support.
Brian Costar is Professor of Politics at the Swinburne Institute for Social Research and a regular contributor to Inside Story (inside.org.au) where this article first appeared.