There is a competition that works like this:
Every time some one enters to your link you get 1 vote.
The problem is that they can catch proxy so I can cheat the system by that.
Any ideas how I can cheat that system?

I'm trying to think if I understand you correctly, and correct me if I'm wrong.. but your dilemma is that you require multiple IP's to click on your link?

if it is then just use hotspots, from like star bucks and mc donalds.. of course you have to drive around to different one's

connect to TOR. write up a simple script with imacros or something similar. get a new ip everytime. (might want to rotate user-agents and referrers as well)

If it's important, you can buy cheap iframe traffic. I can help if you want.

I wonder how they can catch if your using a proxy? I know some sites have proxy shield now, but I wonder if that really protects them? maybe it's just scare tactics which gives minimum protection