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.