The Effect of Third Party Candidates in Presidental Elections Although citizens of the United States have the opportunity to vote for many different offices at the national, state, and local levels, the election of the president of the United States every four years is the focal point of the American political process. The American political system has maintained a two- party system since its inception. Political scientists argue that a two-party system is the most stable and efficient means of running a democratic nation as a mono-party system leads toward tyranny, and a multi-party system creates over- divers