Colorado voters on Tuesday voted in favor of an amendment to the state's Constitution that would completely abolish slavery, striking language that allows slavery or involuntary servitude in the case that it is "a punishment for crime." 

Sixty-five percent of voters voted in support of the amendment, which changes Article II, Section 26 of Colorado's Constitution to state, "There shall never be in this state either slavery or involuntary servitude." Thirty-seven percent of voters voted against the change.

The amendment needed 55 percent support to pass.

A similar amendment failed two years ago because voters were confused about what it meant, NPR reported.