If they only commented on their leaks, that would be one thing, you can't really blame them for not having any Trump documents. But they've given extensive commentary on the email scandal and the FBI investigation, which frankly have nothing to do with their leaks.
I don't doubt there are similar efforts on the part of the GOP or Donald Trump supporters.
Bernie Sanders was subject to vicious propaganda and a generally adversarial mass-media, then when the Democratic nomination was "clinched" by Hillary a sudden swelling of negative media stories on the Green Party's Jill Stein and Libertarian Party's Gary Johnson filled the media channels.
Up until that point, they received almost no media coverage.
This has been the nastiest and most manipulative Presidential election I can remember, though I am only 37 so take that as you will. One thing is certain, hard-core progressives and leftists now know for certain what the DNC and Democrats are really about, and how low they will go to accomplish that.
Recently!!!?
Considering there are hundreds of millions of dollars going into either side of the campaign I'd question the source of any online comment taking a highly partisan position that perfectly fits into party lines. Could be either direct 50-cent armies [1] style astroturfing or regular people influenced by other comments fed elsewhere online, or worse, articles fed to reputable news sites.
Even GCHQ docs from the Snowden leaks showed that five eyes have been successfully experimenting with controlling online conversations since at least 2012. So it's definitely doable with a dedicated team.
This is modern PR. Another thing that sites like HN/reddit increasingly have to contend with to keep content authentic and quality...
[1] https://en.wikipedia.org/wiki/50_Cent_Party?wprov=sfla1