In the United States, Super Tuesday, in general, refers to the Tuesday in February or March of a presidential election year when the greatest number of states hold primary elections to select delegates to national conventions at which each party's presidential candidates are officially nominated. More delegates can be won on Super Tuesday than on any other single day of the primary calendar; accordingly, candidates seeking the presidency traditionally must do well on this day to secure their party's nomination. In 2008, Super Tuesday was February 5; 24 states held primaries or caucuses on this date, with 52% of all pledged Democratic Party delegates and 49% of the total Republican Party delegates at stake. The 2012 Super Tuesday was held on March 6, 2012.
Since Super Tuesday primaries are typically held in a large number of states from geographically and socially diverse regions of the country, Super Tuesday typically represents a presidential candidate's first test of national electability. Convincing wins in Super Tuesday primaries have usually propelled candidates to their party's nomination. The particular states holding primaries on Super Tuesday have varied from year to year.