Elections are central to the struggle for power in democracies, and political campaigns bring meaning to those struggles. Like much of our political landscape, the participants, strategies, and campaign tactics involved in elections have shifted over time. Early campaigns were inexpensive, nonpartisan, and highly personalized events geared toward persuading a small percentage of the population. By contrast, many contemporary campaigns are orchestrated events that entail large sums of money, professional campaign organizations, political parties, interest groups, volunteers, and complicated targeting and marketing strategies involving millions of voters. The one principle that has remained relatively constant is that the candidate who garners the most votes wins. This winner-takes-all principle applied to the campaigns for colonial legislatures held prior to the United States’ founding, and it continues to hold true for most contemporary elections. With some exceptions, most notably the requirement that presidential candidates win a majority of the Electoral College vote, it applies to nomination contests, general elections, and run-off elections.

The types of campaigns that characterize a democracy are shaped by the strategic environment in which they take place.1 This typically includes the constitutional design of the political system, the nature of the offices candidates seek, the laws and rules governing party nominations or general elections, and the relatively enduring aspects of a nation’s political culture involving citizens’ attitudes toward politics, politicians, political parties, and interest groups. The strategic environment also encompasses the methods available for candidates, parties, advocacy groups, and others participants in elections used to communicate with voters. These methods have evolved over time from word of mouth and pamphlets to television advertising to Internet web sites. A final element of the strategic environment is the immediate-and very fluid-political setting. This may involve national factors such as the state of the economy, presidential popularity, and the mood of the public, as well as local factors involving the partisanship and competitiveness of the district where an election is being held, whether an incumbent is seeking reelection, and local conditions and events.