The title of this slim volume makes it sound much more exciting than it is. "Twelve short case studies in real-world political game theory" might be more appropriate. The fundamental point is that voting preferences are not simple, so a bit of engineering can move the outcome. In the first place, the agenda can be rearranged to steer to a particular result. Secondly, strategic voting can often be used to counteract this agenda management. The third mechanism is to reframe the debate, bringing up a new way of looking at the problem so as to lead to a different political result.
The book manages its thesis rather well, through the case studies. The examples range from reasonable behaviour through to the rather morally dubious. The book justifies them all with appropriate realpolitik excuses - it's not clear if the author really believes this, or is just proclaiming the same "the ends justify the means" mentality shown in the examples as an intellectual exercise!
After reading a few books on game theory that take a relatively mathematical approach, this makes a nice contrast. Riker clearly comes from a background of politics and history, and there is heavy grounding in the history of the US political system. The game theory is informal and weak, but the political acumen is clear. If I had to choose one book dealing with real-world game theory, this would not be it. If I had to choose a selection, though, this would make the cut.