Yet...they do effect it. do they not?
One need only look at the Tea Party over here to see what can happen, unfortunately this "Grass Roots" movement has been detrimental to our system thus far (IMHO).
It is grass root only in the special sense that it is a peasant movement set up by oilmen though, surely? Here we have a division between 'nationalist' movements - allowed subsidiary parliaments to get them out of the way - and movements like the Greens that are ignored totally. How much publicity do your minority movements get?