Incumbent

The incumbent is the current holder of a political office. This term is usually used in reference to elections, in which races can often be defined as being between an incumbent and non-incumbent(s). For example, in the Hungarian presidential election, 2017, János Áder was the incumbent, because he had been the president in the term before the term for which the election sought to determine the president. A race without an incumbent is referred to as an open seat.

Etymology
The word "incumbent" is derived from the Latin verb incumbere, literally meaning "to lean or lay upon" with the present participle stem incumbent-, "leaning a variant of encumber, while encumber is derived from the root cumber, most appropriately defined: "To occupy obstructively or inconveniently; to block fill up with what hinders freedom of motion or action; to burden, load."

Incumbency advantage
In general, incumbents have structural advantages over challengers during elections. The timing of elections may be determined by the incumbent instead of a set schedule. For most political offices, the incumbent often has more name recognition due to their previous work in the office. Incumbents also have easier access to campaign finance, as well as government resources (such as the franking privilege) that can be indirectly used to boost a campaign. An election (especially for a single-member constituency in a legislature) in which no incumbent is running is often called an open seat; because of the lack of incumbency advantage, these are often amongst the most hotly contested races in any election. S