Internet trolls paid by political groups (troll farms) have been "rumored" to exist as far back as the 2008 campaign at least. During late 2007 I started to notice how prevalent it was for certain candidates to be attacked in the comments sections of any article written about them. I did a little research into it and found a few people wrote that there existed groups of people paid to write comments.
This of course could not be easily verified, so it was dismissed by the MSM as just a "conspiracy theory." By 2011 or early 2012, I started writing a story that ended up being a novella I titled, Wackos to Obliterate. This ended up as a trilogy. In it, a sub theme of the series is a group of paid trolls. I wrote this before the MSM started to become obsessed by "troll farms" in Russia.
If you're interested, check out the first few chapters of Wackos to Obliterate. On my Steemit home page, there's a link to my Amazon Author page if you're interested in reading the books in the series now.
Currently, I'm uploading a chapter a day on my "beta" branch of a Brautigan Library Kenneth Wayne. Eventually, I'll have all the wackos available for obliteration.