Politics is getting tiring

I am getting tired of seeing all of the presidential candidates fighting among themselves. Sure, you expect to see the different parties fighting each other. But I will never understand why the people in the same party want to fight. I mean, only one of them is gonna go against the other party and they are laying out all this ammunition for other party. I say this because I got on Yahoo and saw this story: Obama criticizes Clinton's past support of NAFTA.