In most states, the 2011 general election falls on November 8. But in Colorado, Election Day this year was November 1. That's due to a quirk in the wording of Colorado's TABOR amendment. TABOR is short for the Taxpayer's Bill of Rights, which was passed by citizen initiative in 1992. Prior to the passage of TABOR, ballot measure votes in Colorado were restricted to even-year general elections. One of the key requirements of TABOR, however, was that all future tax increases would require voter approval, and TABOR changed the Colorado constitution to permit votes on revenue issues in odd years:
Colorado Constitution Article X, §20(3)(a)
Ballot issues shall be decided in a state general election, biennial local district election, or on the first Tuesday in November of odd-numbered years.
For even-year elections, state law specifies that the general election is held on "the first Tuesday after the first Monday in November." That falls on November 8 this year, when most states hold elections. Under the TABOR language, however, Colorado's odd-year election fell on November 1 this year, the first Tuesday in November.