PPP
A presidential preference primary is a statewide process to choose the Democratic and Republican presidential candidates for the November General Election ballot.
Caucus
A caucus is a gathering where local political party members put forth their favored presidential candidates. Caucuses are financially supported by the political parties themselves, as opposed to publicly funded primaries and candidates formally announce their candidacy.
Please Note:
The Nevada Republican Party has barred candidates from participating in its caucuses if they also participate in the primary election.