Midterm election

Apart from general elections and by-elections, a midterm election refers to a type of election where the people can elect their representatives and other subnational officeholders (e.g. governor, members of local council) in the middle of the term of the executive. This is usually used to describe elections to a governmental body (generally a legislature) that are staggered so that the total number of offices of that body would not be up for election at the same time. Only a fraction of a body seats are up for election while others are not until the terms of the next set of members are to expire. The legislators may have the same or longer fixed term of office as the executive, which facilitates an election midterm of the tenure of the higher office.

In the United States, the president and vice president are elected every four years in indirect (electoral college) presidential elections. The legislative bodies of the United States are the Senate (which serves six-year terms) and House of Representatives (two year-terms). The Senate has one third of its members up for election every two years while the House has all its membership up for election every two years. Regarding elections to the United States Congress, the point of reference is the president's term. There are three classes of United States senators; each election replaces one class, hence a "midterm election" appears as one third through the term of one class and two thirds through the other, while still midway the term of a president. In addition to federal legislative bodies, governors of 36 states and three territories are also up for election during a midterm election.

Meanwhile, although the Philippines and Liberia also conduct midterm elections, not all seats in the legislative bodies with elections are contested in a single cycle. This means the winners of such elections take office in their respective legislative bodies that conduct such elections midway through the term of half of the other members, hence for the members who were not up for election, the incoming members take office midway through their terms. This is especially the case in the Philippine Senate, when there are elections every three years to fill half of the 24 seats for a six-year term.

日本の参議院は任期がずらされた選挙方式を採用しているが、衆議院のように任期が固定されておらず、天皇の地位は世襲制である。日本の首相は衆議院によって選出されるが、首相は通常、参議院選挙の結果を受けて職務を遂行し、辞任や内閣改造を行う。

一方、キプロスでは、下院議員は5年の固定任期で選出され、選挙のたびに全員が改選されるが、下院選挙は、大統領自身の5年間の任期の中間に実施される予定となっている。

中間選挙の結果は、現職の行政機関の人気を測る指標となるが、米国ではほとんどの場合、与党が選挙で敗北している。議会制が主流のヨーロッパ諸国では​​、厳密な意味での中間選挙は必ずしも存在しない。そのような場合、地方選挙、地域選挙、欧州議会選挙は、国政選挙の年以外における与党の人気を測る指標としてしばしば用いられるが、必ずしも予定されている国政選挙や大統領選挙のちょうど中間に行われるとは限らない。