Originally Posted by
USMC3197
Mine never responded.
They may not respond, but they (or their staffers at least) read ALL of their constituent mail and often use those inputs to develop their stand on some issues. You will not likely change their mind on some major issue which is a key platform of their party (ex. abortion), but on little-known issues which they don't have expertise or a predefined opinion, a few letters can make all the difference.