I correspond with my elected officials all of the time, via letter, e-mail, telephone and in person.
I always keep my written correspondence to a paragraph or two. Sometimes, it does have an impact (especially in local politics), but other times I feel kind of blown off.
Have you ever thought about expressing your views in a letter to the editor in your local paper? This is another way to get something acrossed to your elected officials and fellow citizens.
Also attend rallies, lectures and protests for your cause. It is a way to meet like minded people with similar ideas. As a group, you usually have more power to sway, than an individual does.
I have a great dislike for Fred Phelps and his antics. I remember when they were protesting a local production of The Laramie Project. My church (Unitarian-Universalist) took coffee and baked goods to the protesters. They refused our generosity, but at least we tried to take the high road.