There really was a Liberal Media Bubble per 538.com
"Instead, it’s that political experts4 aren’t a very diverse group and tend to place a lot of faith in the opinions of other experts and other members of the political establishment. Once a consensus view is established, it tends to reinforce itself until and unless there’s very compelling evidence for the contrary position. Social media, especially Twitter, can amplify the groupthink further. It can be an echo chamber."
Quite a read especially for those of us IN the echo chamber states.