A multi-party swing is an indicator of a change in the electorate's preference between candidates or parties, often between major parties in a two-party system. A swing can be calculated for the electorate as a whole, for a given electoral district or for a particular demographic.to cause to move to and fro, sway, or oscillate, as something suspended from above: to swing one's arms in walking. to cause to move in alternate directions or in either direction around a fixed point, on an axis, or on a line of support, as a door on hinges.

A multi-party swing is an indicator of a change in the electorate's preference between candidates or parties, often between major parties in a two-party system. A swing can be calculated for the electorate as a whole, for a given electoral district or for a particular demographic.to cause to move to and fro, sway, or oscillate, as something suspended from above: to swing one's arms in walking. to cause to move in alternate directions or in either direction around a fixed point, on an axis, or on a line of support, as a door on hinges.