Editor's note: According to this Republican National Committee website "Welcome to the most grassroots-driven platform development effort in the history of American politics! The Republican Party is seeking your input as we develop the policies and principles upon which we should stand for the next four years. On this website, you can share your thoughts, participate in polls, and communicate directly with the policymakers who will be shaping the party's agenda. All comments and feedback will be reviewed and taken into full consideration as we prepare for our convention in Minneapolis-St. Paul."
So, sign up for an an account, login, and start telling them what you think about space. Let's see if the DNC offers a similar service - we'll certainly link to it if they do.
Editor's update: Looks like the Democratic National Committee has something very similar online: "Today the Democratic National Committee and Obama for America unveiled a bold new initiative to involve the American people in the development of the Democratic National Platform. This year, for the first time, voters will have the opportunity to take part in Platform Meetings in all 50 states to help shape the Democratic Platform."