The members of election boards shall be deemed temporary state employees who are compensated by the county in which they serve, and shall receive compensation at a rate established by the board of supervisors, which shall be not less than the minimum wage established in section 91D.1, subsection 1, paragraph “b”, while engaged in the discharge of their duties and shall be reimbursed for actual and necessary travel expense at a rate determined by the board of supervisors, except that persons who have advised the commissioner prior to their appointment to the election board that they are willing to serve without pay at elections conducted for a school district or a city shall receive no compensation for service at those elections. Compensation shall be paid to members of election boards only after the vote has been canvassed and it has been determined in the course of the canvass that the election record certificate has been properly executed by the election board.