Ordinances approved by mayor

Only if an ordinance adopted pursuant to section 31-4-102 (3) or 31-4-302 so provides, any ordinance adopted and all resolutions authorizing the expenditure of money or the entering into of a contract require the approval and signature of the mayor before they become valid, except as otherwise provided in this section. Such ordinance or resolution shall be presented to the mayor within forty-eight hours after the action of the governing body for his signature approving the same. If he disapproves, he shall return such ordinance or resolution to the governing body at its next regular meeting with his objections in writing. The governing body shall cause such objections to be entered at large upon the record and shall proceed at the same or next subsequent meeting to consider the question: "Shall the ordinance or resolution, notwithstanding the mayor's objections, be passed?" If two-thirds of the members of the governing body vote in the affirmative, such resolution shall be valid, and such ordinance shall become a law the same as if it had been approved by the mayor. If the mayor fails to return to the next subsequent meeting of the governing body any resolution or ordinance presented to him for his approval, the same shall become a valid ordinance or resolution, as the case may be, in like manner as if it had been approved by him.