N.J. Stat. § 40:81-7
Four weeks after their election in the case of the first municipal council elected, and on July 1 following all subsequent municipal elections, the members-elect of the municipal council shall assemble at the usual place of meeting of the governing body of the municipality and organize and elect one of their number as mayor. The mayor shall be chosen by ballot by majority vote of all members of the municipal council. If the members shall be unable, within five ballots to be taken within 2 days of said organization meeting, to elect a mayor, then the member who in the election for members of the municipal council received the highest vote, in accord with the manner of canvassing the ballots as herein set forth, shall be the mayor. Should such person decline to accept the office, then the person receiving the next highest vote shall be the mayor, and so on, until the office is filled.
N.J.S. § 40:81-7