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Before 1972 primaries were important, but not critical to selecting a nominee. Half or more of the delegates were party loyalists, and elected politicians. Candidates went into the convention knowing they needed to make deals. In 1968 half the Democratic delegates were chosen before the New Hampshire primary. Humphrey was nominated without running in a single primary.

Today the convention is a rubber stamp of the primary and/or caucus routine. If two or more candidates reached the convention with less than a majority, it could be interesting, but otherwise it is a ceremony.