All they can really do is go around trolling other users with public photos and comments. But, it can be confusing to the recipient to be attacked by other "conservatives". It's also time consuming to clean out your inbox and remove comments from photos, videos, etc...
The best you can do is block and report for harassment, especially when they go into hate speech, which they invariably do.
What can they hope to accomplish by posing as conservatives? I can think of a couple things:
- discourage people from publicly supporting Rick Perry or John Cornyn on Facebook
- put the Tea Party in a bad light. They make some really awful comments.
- plant the idea of dissent amongst conservatives
- keep an eye on what people are saying on the "other side"
I fell for the tactic at first; but the comments that the operatives make do not coincide with the public image their profiles convey. After looking at several of the profiles, I noticed that they were very consistent in their interests with little variance, which is necessary to carry out their aim.
This tactic is possible because Facebook uses the interests you list on your profile to feed you updates that are interesting to you. Thus, by pretending to be conservatives, they don't get extraneous information from people with whom they agree politically. It literally gives them a front row seat to the machinations of the opposition.
I don't expect such tactics will last too long; people will begin to tighten up their circle of Facebook friends and access to their posts to keep the jokers out. But, it will be a while before others catch on and act accordingly.
Be careful to not be baited into posting something inappropriate in the heat of anger. Quietly block and report.