How does the presidential primary differ from those primaries used in state and local nominations?

In presidential nominations, all voters in all states come together to pick a candidate for the presidency of the United States of America. Their votes are cast which each state having a certain number of electoral colleges which tip the state in favor of one candidate or the other. Primary elections occur before general elections. During primary elections, a candidate aligns himself or herself with a party and he or she is either endorsed or loses and drops out of the race. If endorsed, he or she goes on to run in general elections.

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