Just an update....
The Instant Transferable Vote poll that includes 28 Democratic Candidates is still open until July 1st. Currently, Sen. Russ Feingold is edging out Gen. Wesley Clark in the balloting.
You can vote in the election here
If you are confused about how to vote, there are directions at the bottom.
You should know that if you really don't care for a particular candidate, you should not rank them (i.e. leave them off), otherwise they could possibly be the candidate your vote gets cast for.