At this point in the game, so much centers around name recognition. The more times the adcom members sees/hears your name, the more likely it is they'll pull you out when they go through the files again. That's why I recommend being proactive and staying in touch with the admissions committee every 2-3 weeks. Send updates of your recent activities, new recommendation letters, new transcripts, new information that you didn't have a chance to mention in your application essays, and even just general enthusiastic letters about how much you want to attend Dartmouth and (more importantly) why specifically it is the right school for you. I also recommend writing instead of calling -- calls only reach one person (probably a disempowered office asst who can't help your application) while letters and even emails are usually distributed to the committee.
Best of luck!