The main difference is that it is a state wide primary for all voters and candidates. In the primary there are districts and candidates that run in districts or counties where only voters of that district or county can vote for that candidate. That is the way it will be when we reach the general election. But by selecting candidates at a convention all voters will be able to vote in all races regardless of district or county. Voters will also have the choice of NOTA or None Of The Above in all races.