Think in terms of "EXPOSURE", since the "contest" concept here is not set up for real merit competition. Yes, take it with a grain of salt, but you can still gain exposure for your work. I'm not an expert on marketing but I believe that's one of the first steps.
One thing I do is make sure my image gets on the "Leaderboard" page since I'm pretty sure that's where many, if not most people will go to view and vote instead of the actual individual image pages. To insure that my image gets to the leaderboard page, I vote for it myself. I can't depend on anyone else to do that. Some hosts don't want you to vote for your own image, but I don't think they understand the reason for doing it and besides, there should be a "rule" that no one can tell you how to vote!