Reply #21: Technically, the nominee is chosen at the convention

[AlGore-08.com]

And isn't the nominee until all the delegates pledged to vote for him/her do so at the convention.

Kerry toyed for awhile with not accepting the nomination at the convention so that he'd have a longer time to avoid the spending limits imposed on him by federal law, but he eventually decided to accept the nomination at the convention.

The only time a nominee would actually be chosen at a convention would be if there were no nominees who had enough delegates to win the nomination prior to the convention itself. After the first vote, the delegates would be free to change their votes until a nominee was chosen.

The primary system is supposed to let the rank and file Dems chose the nominee, rather than party insiders.