Definition

• Presidential primary elections nominate the candidates for president. They are held in the year leading up to a presidential election. In primary elections, voters choose their favorite candidate, much like a regular election. The state counts the ballots and selects a delegation that represents the voters' preferences. The size of each state's delegation depends on its population.
  
  Potential candidates who win the majority of a party's delegates win the nomination. This is why primaries are so important: If candidates win a majority early on in key states, they win the nomination early in the process.
  
  

Types

• There are two types of primaries: open and closed. Closed primaries are for voters registered to a particular political party. In a Republican closed primary, for example, only registered Republicans can vote for the Republican candidates. States with closed primaries hold a primary for each major political party.
  
  In open primaries, voters may cast their ballot once for a party of their choosing. This means, for example, that a Democrat could vote for a Republican candidate instead of a Democratic candidate.
  
  

Primaries vs. Caucuses

• The confusing thing about primaries is that not all states hold them. Nineteen states hold caucuses, which are similar to primaries. Voters in caucuses select their favorite candidate, and the state selects a representative delegation, but the means is different. In a caucus, voters gather by precinct, county or district and discuss the candidates to make their selection, rather than casting individual ballots.