N.J. Stat. § 40:49-27
Any ordinance authorizing the incurring of any indebtedness, except for current expenses, shall become operative 20 days after the publication thereof after its final passage, unless within those 20 days a protest against the incurring of such indebtedness shall be filed in the office of the municipal clerk, by a petition signed by registered voters of the municipality equal in number to at least 15% of the number of votes cast in the municipality at the most recent general election at which members of the General Assembly were elected, in which case such ordinance shall remain inoperative until a proposition for the ratification thereof shall be adopted, at an election to be held for that purpose, by a majority of the qualified voters of the municipality voting on the proposition, subject to the provisions of R.S. 40:49-10 to 40:49-12.
A petition circulated pursuant to this section shall be subject to the provisions of sections 2 through 5 of P.L. 1986, c. 69 (C. 40:49-27a to 40:49-27c).
N.J.S. § 40:49-27