N.M. Stat. § 6-6-7
It shall be unlawful for the board of county commissioners, the county clerk or any other county official authorized to make purchases to disburse, expend or obligate any sum in excess of fifty per centum of the approved budget for the fiscal year during which the terms of office of any such official will expire; provided, however, that expendtiures or [expenditures for] election expense, record books, necessary office equipment and fuel shall be excepted from the provisions of this act [6-6-7, 6-6-9, 6-6-10 NMSA 1978]. In the event it may be deemed advisable or advantageous to contract for fuel for the entire year, proper precaution must be exercised that a sufficient supply of fuel will be on hand and available for the needs of the incoming officials, or an amount equal to the sum by which one-half the budget item has been exceeded.
NMS § 6-6-7