In electoral politics, a third party is any party contending for votes that failed to outpoll either of its two strongest rivals (or, in the context of an impending election, is considered highly unlikely to do so). The distinction is particularly significant in two-party systems. In any case "third" is often used figuratively, as in "the third parties", where the intent, literally stated, is "the third and succeeding parties". In the United States of America, there have been numerous "third parties". The largest since the mid-20th century are the Libertarian and Green Parties.