Not a public poll please! The only thing a public poll is going to do is tell us who is the most popular contestant. Believe me, I've been through this.
In 2011 I registered on Scenebeta to join the SceneryBeta2011, and there were 2 polls, a public one and a contestant-only poll.
On the contestant-only poll I got a very nice 4th place, but I was new in the community so I didn't have any friends there... as a result in the public poll I got the very freaking last position... below a button tester... below a button smasher... below apps that didn't even work.
Well this is just my experience, and wether you finally open a public poll or not I will still join and see what happens but seriously I will have lost every bit of hope.
Greetings.
PS: Not meant to be spam or anything like that, remove the link if you don't agree but this is the project that I entered the contest with, the one that lost to several button smashers and testers... and I don't think its actually THAT horrible:
https://www.youtube.com/watch?v=hLDAn_WzsE4