need some input for the poll hack

I have a question for you all for my poll hack. I'm wondering what would be the best way to store who voted.

currently I am using a TEXT field with all the ids. This is obviously unefficient when it comes to big sites, where searching would be combersome

I see 2 options - one is to sort the ids and do a binary search to find if you have voted.

or - create a seperate table called pollvotes which would have a entry for each vote. This would allow me to create a "vote history" feature.

so, what do you think?

Just create a voters table and store each person along with the ID of the particular vote that they have participated in.