A marginal seat, or swing seat, is a constituency held with a particularly small majority in a legislative

Legislature

A legislature is a kind of deliberative assembly with the power to pass, amend, and repeal laws. The law created by a legislature is called legislation or statutory law. In addition to enacting laws, legislatures usually have exclusive authority to raise or lower taxes and adopt the budget and...

 election

Election

An election is a formal decision-making process by which a population chooses an individual to hold public office. Elections have been the usual mechanism by which modern representative democracy operates since the 17th century. Elections may fill offices in the legislature, sometimes in the...

, generally conducted under a single-winner voting system. In Canada they may be known as target ridings

Target ridings in the Canadian federal election, 2006

The 39th Canadian federal election was held on January 23, 2006.The target ridings are the ridings that were won by a narrow margin in the preceding election, making them promising campaign targets in the election in question...

. The opposite is a safe seat

Safe seat

A safe seat is a seat in a legislative body which is regarded as fully secured, either by a certain political party, the incumbent representative personally or a combination of both...

.

These seats require a smaller swing

Swing (politics)

An electoral swing analysis shows the extent of change in voter support from one election to another. It is an indicator of voter support for individual candidates or political parties, or voter preference between two or more candidates or parties...

 to change hands and therefore are typically the focus of most campaign

Political campaign

A political campaign is an organized effort which seeks to influence the decision making process within a specific group. In democracies, political campaigns often refer to electoral campaigns, wherein representatives are chosen or referendums are decided...

 resources. The concentration of money and manpower to areas where they will make the most difference is known as targeting

Targeting (politics)

Targeting in politics is widely used in determining the resources of time, money, and manpower to be deployed in political campaigns. Political parties, campaign committees and political action committees prefer to place their resources disproportionately in constituencies where victory is...

.

Strategies for securing swing seats

The creation of policy that will benefit a particular seat, while costing all taxpayers is known as pork barrel

Pork barrel

Pork barrel is a derogatory term referring to appropriation of government spending for localized projects secured solely or primarily to bring money to a representative's district...

ing.

Political parties often face tension between the holders of marginal seats and safe seat

Safe seat

A safe seat is a seat in a legislative body which is regarded as fully secured, either by a certain political party, the incumbent representative personally or a combination of both...

s. Holders of safe seats tend to get far less discretionary resources—governmental as well as political—from their political party than do holders of marginal seats.

A similar phenomenon happens in United States presidential election

United States presidential election

Elections for President and Vice President of the United States are indirect elections in which voters cast ballots for a slate of electors of the U.S. Electoral College, who in turn directly elect the President and Vice President...

s, where the Electoral College system means that candidates must win states rather than votes. Again, resources are concentrated towards the swing state

Swing state

In United States presidential politics, a swing state is a state in which no single candidate or party has overwhelming support in securing that state's electoral college votes...

s with the smallest majorities.