thumb|upright=1|Political parties like the Romanian Communist Party can arise out of, or be closely connected to, existing segments of society, such as organizations of workers. One of the core explanations for the existence of political parties is that they arise from pre-existing divisions among people: society is divided in a certain way, and a party is formed to organize that division into the electoral competition. By the 1950s, economists and political scientists had shown that party organizations could take advantage of the distribution of voters' preferences over political issues, adjusting themselves in response to what voters believe in order to become more competitive. Beginning in the 1960s, academics began identifying the social cleavages in different countries that might have given rise to specific parties, such as religious cleavages in specific countries that may have produced religious parties there.
thumb|upright=1|Political parties like the Romanian Communist Party can arise out of, or be closely connected to, existing segments of society, such as organizations of workers. One of the core explanations for the existence of political parties is that they arise from pre-existing divisions among people society is divided in a certain way, and a party is formed to organize that division into the electoral competition. By the 1950s, economists and political scientists had shown that party organizations could take advantage of the distribution of voters' preferences over political issues, adjusting themselves in response to what voters believe in order to become more competitive. Beginning in the 1960s, academics b:egan identifying the social cleavages in different countries that might have given rise to specific parties, such as religious cleavages in specific countries that may have produced religious parties there.