The astroturfing seems so obvious (rapid ramp-up) that I had to wonder if Romney's campaign was actually behind it. Why not pay a little more to do a good job -- at a minimum, ramp-up over time. Two possibilities (among many, I suppose) are that an Obama supporter paid for the fake followers so that a story could be planted about Romney's deceptive tactics. Another possibility is that a fake user farm set-up its fakes to follow a few random, high-profile users to make the fakes seem more legit. If this was the case, why choose Romney but not Obama? Based solely on the data, we can't know what actually happened, but it doesn't seem like the article's conclusion was drawn after exploring alternate possibilities and finding reasons to dismiss them.