The voting system in New Zealand uses the Mixed Member Proportional, MMP. In this system, everybody gets two votes, one for the party vote and one for the electorate of your region.
Party Vote: In parliament there is 120 seats, it goes on what percent of votes your party gets, thats the percent of seats you get. If you get under 5%, your party will not get in but, if you have someone from your party who gets into an electorate seat you will get the percent of seats your got with an electorate seat. To get into government, you have to get more then 50% of the votes. If you have the most, but don't get over 50%, you need to make a co-alition with other partys to hit the 50% marker.