DENVER (AP) -- Colorado's personhood amendment has suffered a setback.

The Secretary of State's office says it made a mistake on the deadline to turn in signatures and moved it up by three days. The new deadline is Feb. 12.

Gualberto Garcia Jones, director of Personhood Colorado, said Friday the mistake could be costly because the last week of a campaign is the most important.

In 2008, Colorado voters decided 3-to-1 against a similar measure that would define fertilized human embryos as people in the state constitution and bar abortions.

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