the system determines the order of candidates. The has 245 members (248 from 2022), elected for a fixed six-year term, 147 (2022–: 148) members by single non-transferable vote (SNTV) in 45 single- and multi-seat constituencies (most are prefectures, two combined constituencies comprise two neighbouring prefectures each) and 98 (2022–: 100) by proportional representation (by D'Hondt method) with optionally open lists in a single, nationwide constituency. are usually held once every three years. In staggered elections, half of the House of Councillors comes up for election every three years in elections. The term is fixed, the House of Councillors cannot be dissolved. This, too, is a parallel electoral system. Dual candidacies are not allowed. As in House of Representatives elections, voters have two votes: In the majoritarian election, the vote has to be for a candidate, but in the proportional election, the vote may be for either a party list or a single candidate; in the latter case, the vote counts as both a vote for the party list (to determine proportional seat distribution), and as a preference vote within that list (to determine the order or proportional candidates within that list). The district magnitudes in the majoritarian tier vary between one and six, dependent on, but not fully proportional to the population of each prefecture. In single-member constituencies, SNTV becomes equivalent to first-past-the-post, whereas seats are usually split between different parties/alliances in multi-member constituencies (and in the proportional constituency by definition). Therefore, the are more likely to swing the election result and often receive more media and campaign attention. The proportional election to the House of Councillors allows the voters to cast a preference vote for a single candidate on a party list. The preference votes strictly determined the ranking of candidates on party lists before 2019. Since the 2019 election, parties are allowed to prioritize individual candidates on their proportional list over voter preferences in a . In the 2019 election, almost all parties continued to use completely open lists; exceptions were the LDP which used the "special frame" to give secure list spots to two LDP prefectural federations affected by the introduction of combined constituencies in 2016, Reiwa Shinsengumi which used it to give secure list spots to two candidates with severe disabilities, and the minor "Labourers' Party for the liberation of labour". The electoral cycles of the two chambers of the Diet are usually not synchronized. Even