In the world of grand political change, three or four years is nothing. Don't give up hope yet. The Demand Progress folks are committed and have a good sense of what it takes to bring about political change in a democracy. Please support them.
And believe it or not, legislators do watch those calls and emails––especially calls. All of them of them will tell you that the perception of a groundswell of support or opposition to an issue is enough to start to sway minds on Capitol Hill. Don't give in to cynicism.