Because gerrymandering relies on the wasted-vote effect, the use of a different voting system with fewer wasted votes can help reduce gerrymandering. In particular, the use of multi-member districts alongside voting systems establishing proportional representation such as single transferable voting can reduce wasted votes and gerrymandering. Semi-proportional voting systems such as single non-transferable vote or cumulative voting are relatively simple and similar to "first past the post" and can also reduce the proportion of wasted votes and thus potential gerrymandering. Electoral reformers have advocated all three as replacement systems.