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Anthony Downs' rational-choice model of political parties, as presented in his seminal work "An Economic Theory of Democracy" (1957), posits that political parties are vote-maximizing entities that adjust their policies and positions to attract the broadest possible base of support. The primary objective of parties, according to Downs, is to win elections. They do this by assessing voter preferences, represented as a distribution along a political spectrum, and then situating themselves at the median of this distribution to appeal to the majority of voters. This approach often results in convergence of party platforms, especially in a two-party system, as both parties strive to capture the median voter, a phenomenon known as "Downsian convergence." The model assumes rational behavior on the part of both parties and voters, with parties seeking to maximize votes and voters seeking to maximize their utility by supporting the party closest to their policy preferences.