Hmm maybe I'm wrong here but every elective I've seen, even the very competitive ones, has its places allocated based on how early you apply and how whether you are willing to pay the fees (up to '000s/week in the US). You're just a student - they aren't employing you. But maybe I'm wrong in some cases - you specifically talk about a "program" rather than what most electives are (placements) so perhaps you have something specific in mind?
In any case - CV building is normally based on the same things - prizes, audits, teaching, posters, publications, extra degrees. It early in your training, probably the best thing you can do CV-wise is to try to get a couple merits/distinctions in exams. If you wanted to do something extra helping out ward staff with audits or asking around about research etc is probably your best bet.