New Jersey Statutes § 19:6-17 County board of elections, membership, appointments, compensation

a. The county board shall consist of four persons, who shall be legal voters of the counties for which they are respectively appointed. Two members of such county board shall be members of the political party which at the last preceding general election, held for the election of all of the members of the General Assembly, cast the largest number of votes in this State for members of the General Assembly, and the remaining two members of such board shall be members of the political party which at such election cast the next largest number of votes in the State for members of the General Assembly. By a majority vote of the full membership of the board of county commissioners, the board of county commissioners may opt to increase to six persons the membership of the county board of elections. The two new members shall be legal voters of the counties for which they are respectively appointed. If a board of county commissioners votes to increase the membership of a county board of elections to six persons, the board of elections shall consist of an equal representation between the political parties which at the last preceding general election, held for the election of all of the members of the General Assembly, cast the largest and next largest number of votes in this State for members of the General Assembly. No person who holds elective public office shall be eligible to serve as a member of the county board during the term of such elective office. The office of member of the county board shall be deemed vacant upon such member becoming a candidate for an office to be voted upon at any primary, general election or special election, except for nomination for or election to membership in any county committee or State committee or for nomination for or election as a delegate at large or alternate delegate at large, or district delegate or alternate district delegate to any national political convention, such candidacy to be determined by the filing of a petition of nomination duly accepted by such member in the manner provided by law.

b. In all counties, the county board of elections may appoint some suitable person as clerk of the board, and may also appoint any additional office employees, including a director of such employees, it deems necessary, subject to approval by the board of county commissioners of the respective county and to the budgetary process required pursuant to section 11 of P.L. 2015 , c. 249 (C.19:6-21.1). The compensation of the clerk, the director, and office employees of the county board of elections shall be in an amount recommended by the county board of elections and subject to the approval of the board of county commissioners.