The earliest method of nominating a candidate for political office was known as a caucus or convention
A closed-vote primary (restricted to party members)
The nominating method that is oldest is the 'self-announcement.' This is when the candidate announces his or her intention to run for an elected office.
Caucus, Nominating Convention, or Primary
The nomination or designation of candidates for public office by direct popular vote rather than through the action of a convention or body of elected nominating representatives or delegates. The term is applied both to the nomination of candidates without any nominating convention, and, loosely, to the nomination effected, as in the case of candidates for president or senator of the United States, by the election of nominating representatives pledged or instructed to vote for certain candidates dssignated by popular vote.