I suspect this is more a result of the media's heavy pro-Clinton bias rather than any overt attempt by Facebook. Remember that the mainstream media is ultimately the primary driver of these algorithms.
That's really a pretty useless analysis. By that metric, the media had an overwhelming bias towards Lincoln Chaffee.
In fact, it directly supports the scenario the OP brought up. Frequently Bernie Sanders will bring something up and then the media focuses its article on Hillary's response (even if that article might sometimes be unflattering).
What this shows is the media has a positive bias towards Kasich and Sanders, neither of which were received as such by voters. What it also shows is media bias doesn't always win votes or elections.
> What this shows is the media has a positive bias towards Kasich and Sanders, neither of which were received as such by voters.
No, what it shows is that the media writes way more articles about Clinton, positive and negative.
Imagine the media writes 2 articles about Sanders, one negative and one positive. And then it writes 20 about Clinton, 11 negative and 9 positive. Who is it biased in favor of?
http://www.vox.com/2016/4/15/11410160/hillary-clinton-media-...