You should focus on the matters that are relevant. Normally if you are contacting a representative, it is because you have some issue with a an aspect of government that is negatively affecting your life and you want their specific aid in achieving something, and something that is within their power. or within their sphere of influence. Or you want to inform your representative on some matter which you feel that they are unaware.
Your voting history is probably irrelevant.
So do include a clear statement of the problem, any relevant details about what you have already done to solve it, and specific requests for what you would like the representative to do. Engage-Present-Inform-CallToAction (EPIC). Don't include your voting history, or any veiled or open promises of future support.