The open ticket system is a form of fair representation voting that combines the benefits of fair and proportional representation with simplicity for voters and election administrators. Every voter votes for exactly one candidate in a partisan election, and the party whose candidates win a majority of votes in the district always win a majority of seats, while smaller groups can also elect their fair share. When used internationally, open ticket voting is known as the unordered open list system.
In an open ticket election, voters cast one vote in a partisan election to elect multiple candidates at-large or in a multi-winner district. The open ticket method in multi-winner elections is a form of fair representation voting.
As in ranked choice voting, if any candidates win more than a certain share of votes, called the threshold, then those candidates are elected. The threshold is the number of votes that guarantees that the candidate will win, because it would be mathematically impossible for them to lose. For example, in a three-winner district, the threshold is 25%, because if one candidate receives more than 25% of the votes, then it is impossible for three other candidates to beat them. In a four-winner district, the threshold is 20%; in a five-winner district, it is about 17%.
Unlike ranked choice voting, voters do not rank candidates. Instead, votes for candidates from one political party help elect other candidates from the same political party. For example, if one political party's candidates collectively receive 60% of the vote in a three-seat district, that party will win two out of three seats, and the two candidates elected will be the two candidates from that party with the most votes. If another party received the other 40%, that party would win the remaining seat, and its top candidate would be elected.
After counting votes and electing candidates above the threshold, administrators would use a proportional representation formula, like the Jefferson's method (named after Thomas Jefferson, who introduced it for use in allocating seats in the House of Representatives in 1791), to determine how many seats to award to each party. Then, the highest vote-getters from those parties are elected. Independent candidates can still run and win election by receiving more votes than the threshold.
Additionally, candidates should be able to optionally list a second back-up political party, in the tradition of fusion voting. That way, if a smaller political party's candidates do not receive enough votes to win a seat, then their votes can help elect candidates from their back-up parties instead.
Because open ticket voting involves only casting one vote for one candidate, it can be administered using any existing voting equipment, and votes can be counted at the precinct level before being reported.
The open ticket system is based on the method used for parliamentary elections in Finland, there called the "unordered open list system." Similar methods are used in Brazil and in Latvia. Finland divides into multi-winner districts that elect between six and 35 members (with one autonomous administrative region electing a single member as well), demonstrating how the open ticket method can comfortably accommodate elections with large numbers of candidates and a large number of elected seats.