The district magnitude refers to the number of legislative seats assigned to a district, ranging anywhere from the exclusive use of single-member districts to a system where the entire country functions as a single district. District magnitude is the primary determinant of an electoral system’s ability to translate votes cast into seats won proportionally.
The district magnitude also has an impact on political parties, candidates, and campaigning. Small district magnitude, for example, fosters stronger links between individual candidates and their local constituencies. On the other hand, large districts give a stronger proportionality, and when more persons are elected from one district, they are more likely to represent various points of view, so more voters will feel that their opinion is represented in the legislature. District magnitude thus has an effect on the extent to which voters feel that their views are represented.
Large districts (together with a relatively small number of parties) increase party magnitude, the number of representatives from one political party elected from the district. This tends to affect candidate selection by political parties, since if the party magnitude is large, it is more likely that the legislature will consist of members from different ethnic and social groups, both sexes, etc. since parties will feel that they can win the most seats by presenting a wider variety of candidates.
The district magnitude also has implications for campaigning. If the district is small and the party magnitude less than one, political parties may decide to spend their campaign resources elsewhere instead of “wasting” them in districts where they are not likely to win any seat.
Because of this, there has been a lively debate about the best district magnitude. The systems which want to achieve the greatest degree of proportionality will use very large districts, because such districts are able to ensure that even very small parties are represented in the legislature. In smaller districts, the effective threshold is higher.
The problem is that as districts are made larger—both in terms of the number of seats and often, as a consequence, in terms of their geographic size as well—the linkage between an elected member and his or her constituency grows weaker.
Large districts can have serious consequences in societies where local factors play a strong role in politics or where voters expect their members to maintain strong links with the electorate and act as their ‘delegate’ in the legislature. Accountability can be diminished and people can become disengaged from politics if they cannot clearly see who represents their region or district in the legislature.
