This sounds similar to our high school. We have 200 students, and the A.D. and administration basically take a collective dump on cross country. We have fall baseball in this state, but it doesn't count for anything since the state champs are in the spring...but boy! you ought to see the A.D. and admin slobber all over themselves for that. I digress...
I'm not the coach, but the I help out in an unofficial capacity organizing workouts in the summer, "unscheduled" practices, etc. One of the things that has worked in our town is slowing building community support. We meet every night in the summer, at the track, at seven o'clock. Kids, parents, and even other adults who run in the community show up to run and socialize. We are a town of 800, and on a good night 30 people will show up. We usually have popsicles waiting, throw the football around after the run, etc. We've had friends of the program organize raffles to raise funds for traveling to big meets, etc. too.
We've gone from one runner in 2009, to boys and girls sweeping state titles two years ago. There are 12 boys out, and six girls out this year. There are six junior high boys and seven junior high girls out. Just being positive and visible goes along way.