Personally, I think it's a great idea. Unfortunately, too many people are either too lazy or disillusioned to actually try to change anything.
The thing is that something like writing or calling a Congressman's office takes 5 minutes out of your day and costs you NOTHING. Your duty as a citizen does not stop at the polls.
For the love of whatever higher power in which you believe, take the time to let it be known that you're holding your elected officials responsible for their actions. They're supposed to be representing you. How can they do that if you don't tell them what you want?
Think about it.