This paper analyzes the trade policies in the voting equilibria under different electoral rules in a small open economy with a fixed factor of production. Specifically, we consider an economy in which economic rents exist in the long run due to a fixed supply of the factor of production. In this economy, each voter has its own share of the factor of production. We find that the equilibrium trade policy under proportional elections depends on the sum of the product of each group`s density and the group`s share of the factor, and is also affected by parameters under some conditions. However, under majoritarian elections, trade policy in equilibrium depends only on the middle group`s fraction of the specific factor if the middle-share group is dominant in one of the districts.