A landslide victory is an electoral victory in a political system, when one candidate or party receives an overwhelming supermajority of the votes or seats in the elected body, thus utterly eliminating the opponents. The winning party has reached more voters than usual, and a landslide victory is often seen in hindsight as a turning point in people's views on political matters.
Part of the reason for a landslide victory is sometimes a bandwagon effect, as a significant number of people may decide to vote for the party which is in the lead in the pre-election opinion polls, regardless of its politics.
The term is borrowed from geology, where a landslide takes almost everything with it on its way.
In a deliberative assembly, votes that are expected to be landslides in one direction or another are typically decided by voice vote.