Deviating elections are elections in which a fraction of the majority-party voters temporarily crosses party lines because of the influence of short-term political factors, causing a swing in the results of an election in favor of the minority party candidate. Deviating elections can cause an electoral landslide.
Deviating elections can occur gradually or suddenly and lead to a change in government. When deviating elections occur, the minority party temporarily assumes power from the dominant political party; however, no long-term shift that would turn the minority party into the majority party occurs. The temporary issues and factors that cause dominant party voters to vote for the minority candidate of the opposition party, but not change their party affiliation, characterize deviating elections.
As the temporary factors and issues in a deviating election recede, in the next election, the majority party voters typically return to their party. If the voters permanently shift away from the dominant political party toward the minority party for several elections, the original election in which the swing occurred is referred to as a realigning election. When the party voters from the dominant political party return to their party after a deviating election and vote a majority party candidate into office, this is referred to as a reinstating election. When this occurs, the dominant party is reinstated.