That has always been the status quo. You just don't know it.
In the last election 54 million people voted for candidates from the left. 51 million voted for candidates on the right. Bush got over 50 million of those on the right. Gore got nearly 51 million on the left. Other leftist candidates got 3 million leftist votes. The far left elected bush.
What you fail to understand is that the TWO big parties have written all the election laws for the last 140 years. They are all designed to help the two major parties stay in power.
They purposely fixed the law so that when the left splits off in anger with the left it elects the right. That makes the left very angry with the right. So the left becomes united in the next cycle and elect the left.The fringes get angry when their side is in power, so that causes a few million split and that elects the other party. The same thing happens to the right and the left. That is why both the left and right support it.
When there are more people on the left than their are on ther right,as there are now, the right moves toward the left until the population is evenly split. If the population starts to move to the right the Left moves to the right until the voters are evenly split.
People like you are clueless about how our system was constructed.