(1) Except as otherwise provided in subsection (3) of this
section, a marriage is valid in this state if:
(a) It is licensed, solemnized, and registered as provided
in this part 1; and
(b) It is only between one man and one woman.
(2) Notwithstanding the provisions of section 14-2-112,
any marriage contracted within or outside this state that
does not satisfy paragraph (b) of subsection (1) of this
section shall not be recognized as valid in this state.
(3) Nothing in this section shall be deemed to repeal or
render invalid any otherwise valid common law marriage between
one man and one woman.
(Colorado Revised Statutes Ann. Section 14-2-104)
CONSTITUTION
Only the union of one man and one woman shall be valid or recognized as a marriage in the state of Colorado.
(Colorado Constitution, Amendment #43, approved by 56% of voters on Tuesday, November 7, 2006)