No doubt the answer will depend on the idiotic premise that FR is just chock-filled with people who have nothing better to do with their time than to hang out on this increasingly irrelevant website and canvass for Vladimir Putin.
Russia’s propaganda does include a social media aspect, they pay people to troll sites pushing Putinism. Not that it happens here, but on some threads it can seem like paid trolling.
http://www.buzzfeed.com/maxseddon/documents-show-how-russias-troll-army-hit-america
http://www.nationalreview.com/article/375899/putins-propaganda-campaign-jillian-kay-melchior
Here's how President Obama's head of the Office of Information and Regulatory Affairs and author of "Repulblic.com," Cass Sunstein, describes FreeRepublic.com as "group polarization," where people segregate themselves so effectively online with other like-minded thinkers that they create an echo chamber where the group's worst and most malevolent opinions get reinforced and strengthened. "We might want to consider," Sunstein startlingly told the Times recently, "the possibility of ways of requiring or encouraging sites to link to opposing viewpoints."
http://dir.salon.com/story/politics/feature/2001/06/25/freepers/
It’s a little more complicated than that: some are paleos, some are paultards, some are peaceniks/isolationists, some are putinistas, and some see a conspiracy behind everything (the bankers, etc.). That they all toe the Kremlin line simply makes calling them Russians a form of shorthand.