Let's see Bikini contest = male audience which means you need a good crowd starting music, preferably something that would be played in a stadium. Shoot, I have a song running through my head, I think it's mainly instrumental and starts with the "Let's Get Ready to Rumble...". ESPN has put out a couple of sport anthem CD's, shouldn't be hard to find. You might even look into some more rock-type WCS. "Let's go Girls" is mainly danced as a WCSwing, but has enough hits and lyrics that are fun to play with, and a strong enough beat you can do a cha-cha to it.
Mainly, you're goal is to please the audience, pick a song that gets them rowdy, and that you don't mind acting to. Because that'll be more of what you will be doing, a little shimmy, a little pose, and a whole lot of acting. So concentrate on your arms, head, and hips as much as possible. Because as my teacher says, "once you get out the studio door, not a whole heck of a lot of people know the difference between good technique and bad technique. Their just impressed you can dance." They do know a good show though.
Good luck,
-TheDitz