In primary elections, you are entitled to vote the official primary election ballot of the political party you are registered with and no other (FS 101.021)
You must be registered with your party of choice 29 days before a primary election (FS 97.055)
All registered voters can vote in a primary election, regardless of which major or minor political party they are registered with or even if they are registered without a specific party affiliation when:
All the candidates for an office have the same party affiliation and the winner of the primary election will not face any opposition in the general election (i.e. no write-in candidates have qualified).
The race is nonpartisian(i.e. prohibited from qualifying or campaigning based upon party affiliation)(e.g. judicial and school board officies, nonpartisan special districts or local referendum questions).
At a general election, you may vote for any candidate or question on the ballot, regardless of party affiliation.