Young people are scientifically proven to be more liberal than old people. I can almost guarantee you that there aren't tons of old people using twitter. So based on the age range that is using twitter, then twitter should appear to be more liberal than conservative. A quick google shows the biggest average age group at 25 - 34. If you actually limited that to people actually posting on Twitter, I would bet good money that it is the younger end of the spectrum that is actually using Twitter. Yeah, I'm on Twitter and I'm older. It's just installed on my phone and I hardly ever actually use it. "Old" conservatives I know hardly even know what Twitter is, much less how to use it. Kind of like me with Snapchat. I know exactly what it is. I have never used it.