West virginia constitution
Article VI: the legislature
Section 50

The Legislature may provide for submitting to a vote of the people at the general election to be held in 1876, or at any general election thereafter, a plan or scheme of proportional representation in the Senate of this state; and if a majority of the votes cast at such election be in favor of the plan submitted to them, the Legislature shall, at its session succeeding such election, rearrange the senatorial districts in accordance with the plan so approved by the people.