According to the United States Constitution, a presidential election is to be held once every fourth year. The process of electing a President and Vice-President begins long before Election Day. Candidates from both major and minor political parties and independent candidates begin to raise money and campaign at least one year in advance of the general presidential election. To officially represent a political party, a candidate must be nominated by that party.

This primary nomination process is a contest that often produces factions within political parties. These divisions impact the policy stances and agendas of the candidates running for nomination as they attempt to garner the support of party leaders and activists. The nominating process officially begins with the first state primaries and caucuses, which usually occur in February of the election year. It is at these local events that voters are given their first chance to participate in electing the nations next President.

Many factors influence who will ultimately become the candidate for a party. The public's perception of the candidates is influenced by such things as media reports, public opinion polls, candidate preference surveys, and advertising. These factors will help determine the perceived strengths and weaknesses of the candidates in the months leading up to the caucuses and primaries.