Wisconsin constitution
Article XII: amendments
Section 2

If at any time a majority of the senate and assembly shall deem it necessary to call a convention to revise or change this constitution, they shall recommend to the electors to vote for or against a convention at the next election for members of the legislature. And if it shall appear that a majority of the electors voting thereon have voted for a convention, the legislature shall, at its next session, provide for calling such convention.