Two Party Systems

Why do we have a two party system.There is no need for it.The government is to be for the people.We have no need to have two party system and they are working for the wealthy,not the poor.So we pay taxes to put politicans in place to lobby against the poor and middleclass.I say middleclass,because they are to dumb to see that auto insurance is to high,prescription drugs,mortgage rates,health insurance etc is to damn high.The current politicans on both sides are trying to kill off the poor,and make the middleclass eventually become poor.