Keep other political issues far, far away.
For msot of the candidates of any general political viewpoint any rail issues, wheter rail transit, long distance rail, or any other thing rail related are very minor issues of interest to only a very small number of people and will be treated accordingly. What you don't want to do is make it appear that rail issues are married to or part of the same package as issues of greater concern regardless of what these issues. (Using the following only as examples, do not let it get in the same package with gun control or anti-gun control, pro life or pro abortion, or anything else of the far more hot-button issues. If you are heavily involved in either one of these on either side, using these only as examples, then do not identify yourself to the politicians, at least, as having strong views on rail issues.) In your pro-rail promotion, it is perfectly fine to raise the issue of reduced use of fossil fuels, air polituion, road congestion, airport congestion, and anything related, but I would strongly recommend you not mention "global warming" or "climate change". The fuel use, air pollution, and congestion issues are obvious, serious, and real even to those who are skeptics concerning warming and change issues. Recognize that you are in the real world and are going to find anybody politician or otherwise with whom you will be in 100% agreement. "Do not the striving for perfection drive out the good." This is not heaven. Perfection does not exist here. Now a political statement from me: The "environmentalists" are not our friends when it comes down to doing something. They may like the concept of rail in concept as reducing the human "fotprint" in general, but when it comes to actuall building something, they seem to be able to find no end of things wrong with whatever is being planned. They also seem to be, either themselves used by those opposed to the rail line in general, or else their concepts and regulations are misused by those that really care nothing about the environment but simply want to stop the porject.