Express Internet Prohibition: The response to this question goes to whether a state has adopted a specific law criminalizing the offering and/or playing of gambling games offered over the Internet. The fact that a state has not passed a specific law does not make participation in or offering of gambling over the Internet legal under the laws of that state. The question is a complex one and is addressed in several of the articles included on this site. http://www.gambling-law-us.com/State-Law-Summary/
There are several states that have specific Laws for express internet gambling... Illinois, Indiana, Montana, Nevada, Michigan, New Jersey, South Dakota