Only voters who are registered members of the two major political parties (Republicans and Democrats) may vote for their respective party's candidates in a primary election. Registered minor political party voters and voters without party affiliation are not eligible to vote for major party candidates in a primary election.
However, Article VI, Section 5(b), Florida Constitution, provides that if all candidates have the same party affiliation and the winner will have no opposition in the general election, all qualified voters, regardless of party affiliation, may vote in the primary election for that office. This is known as a Universal Primary Contest.
Nonpartisan judicial and school board offices, nonpartisan special districts and local referendum questions are included in some primary elections. All registered voters, including those without party affiliation and minor political party voters, are entitled to receive and vote these ballots. At general elections, all voters receive the same ballot and may vote for any candidate or question on the ballot.
(see sections 100.051, 100.061 and 101.021, Florida Statutes, and Article VI, Section 5(b), Florida Constitution)