Todd Donovan, "Mobilization and Support of Minor Parties: Australian Senate Elections," Party Politics, 6 (October 1999), 473-486.

First Paragraph:

Party systems typically reach equilibrium where a fixed number of parties endure over a relatively long time period (Converse, 1969). In nations using plurality rules, the number of parties is often as low as two or three (Lijphart, 1994: 105). Most small parties exist briefly relative to the history of a party system elected under plurality rules, unless their strength is concentrated in distinct geographic regions. Although some might temporarily disrupt a party system's equilibrium, nearly all remain minor players.

Figures and Tables:
Table 1: Leading minor parties in Australian Senate contests, 1922-98
Figure 1: Mobilization of Communist candidates, 1931-61
Figure 2: Variation in Australian Democrat Vote, 1977-98 (national)
Table 2: Estimate of minor-party mobilization in Australian Senate Elections, 1922-98
Table 3: Estimate of minor-party support in Australian Senate elections, 1922-98

Last Paragraph:
All of this means that the system of competition among the minor parties, and between the minor and major parties, is highly dynamic. Few small Australian parties remain on the scene for extended periods of time. Institutional conditions present them with opportunities to mobilize and respond to short-term forces that breed discontent with established parties. When the short-term (or cyclical) conditions that gave birth to these parties are gone, so are many of the parties. Yet institutional conditions remain in place that allow for the subsequent mobilization of other small parties when cyclical forces are back in place. The Senate, and some houses of the states' legislatures elected by PR, provide an institutional forum where these parties can occasionally thrive.