the point is "first past the post" voting has been the only form of voting we have had since the begining of america. despite this we have had 8 different parties win presidential election and even in recent history just a few decades ago we have a thid party come **very** close to winning.
I'm not claiming a third party vote is likely by any means. but it is certainly possible with the current system of voting, should the proper mentality arise in the people.