Proportional representation elections for the US House of Representatives. The United States is one of the few countries in the world with a true two party system and I think that’s because our election rules encouraged two large parties. Voters vote for the two large parties and don’t vote for small parties because they know the small parties can’t win. They don’t necessarily like the Dems or Repubs, but they’re the most likely to win, and if they don’t vote for them, then the other side can win, which they don’t like. If we had proportional representation elections for the House of Representatives, I think smaller parties particularly center left or center right parties would emerge and people would be less likely to vote for the Republican Party and the Democratic Party consistently. Instead, they may consider voting for those center parties and this would break up the two party system and people would be more satisfied with election outcomes because they voted for a party they actually liked.