Shifts in voters’ preferences over time also help explain voting cycles—the swings common in democratic countries in political control between one party, located slightly to the left of center, with the other being slightly right of center. Each then advertises itself as the party of the future and hopes that circumstances will move more voters in its direction. The two parties, being reasonably comfortable with each other, then compete through expensive campaigns.

 

A typical congressional campaign now requires a war chest of over $1 million. One recent U.S. Senate candidate spent almost $27 million campaigning for a job paying about $260,000 annually—and lost. Campaign spending on television spots alone now exceeds $140 million in presidential election years. Such barriers frustrate third-party challenges to either dominant party. Another barrier to political competition entails making it hard any third party to get on the ballot. For example, the dominant parties may enact laws requiring petitions to be signed by huge numbers of voters before a third party can be on the ballot if it received less than 5% of the votes in a prior election.

 

Third parties tend to be launched from the extremes of the political spectrum and to be based on single issues. If a third party begins to attract more voters than either dominant party expected, the closest major party commonly adopts a moderate version of the third party’s position. If leaders of a third party seriously want political power, it tends to become more moderate and is eventually absorbed by the closest major party. Thus, mature democracies usually operate under the control of two major parties. Third parties rarely displace major parties, and then only when a major party fails to respond to changes in voter preferences.

 

Two-party systems also tend to foster political stability. Italy has had numerous parties, and after the end of World War II, the typical government lasted less than a year. As we have seen, politicians and political parties tend toward the middle-of-the-road in an effort to capture votes. Once politicians are in office, can we expect them to shed their self-interest and work primarily for the common good of their constituents?