You can see the current Steem witness list at https://steemd.com/witnesses and https://steemian.info/witnesses 

Thankfully Steem voting is stake based to prevent just that sort of one-user-one-vote sybil attack. He's currently appealing (begging) different communities to get more votes for his sockpuppet attack witnesses. And as this post explains he was able to get exchanges to power up their customer's funds and proxy to his voting account, even though those exchanges should know better and perform due diligence before doing something like that.