Colorado constitution
Article IV
Section 11

Every bill passed by the general assembly shall, before it becomes a law, be presented to the governor. If he approve, he shall sign it, and thereupon it shall become a law; but if he do not approve, he shall return it, with his objections, to the house in which it originated, which house shall enter the objections at large upon its journal, and proceed to reconsider the bill. If then two­ thirds of the members elected agree to pass the same, it shall be sent, together with the objections, to the other house, by which it shall likewise be reconsidered, and if approved by two­ thirds of the members elected to that house, it shall become a law, notwithstanding the objections of the governor. In all such cases the vote of each house shall be determined by ayes and noes, to be entered upon the journal. If any bill shall not be returned by the governor within ten days after it shall have been presented to him, the same shall be a law in like manner as if he had signed it, unless the general assembly shall by their adjournment prevent its return, in which case it shall be filed with his objections in the office of the secretary of state, within thirty days after such adjournment, or else become a law.