Every U.S. state except one follows the federal model of a bicameral legislature (consisting of two houses, like a Senate and a House of Representatives). The exception is Nebraska. Since 1937, Nebraska has operated with a unicameral legislature, meaning it has only one legislative chamber. Its members are called 'Senators.' Furthermore, it is the only state legislature in the US that is officially non-partisan; candidates do not have political party affiliations listed on the ballot. This system was adopted during the Great Depression to save money and increase government efficiency by removing the 'conference committees' needed to resolve differences between two houses.