Illinois’s move in the sports-heavy state is the latest blow to the sites which are fighting a ban imposed in New York where attorney general Eric Schneiderman issed them with “cease and desist” notices. The ban has been lifted after a stay on an injunction, pending further action. The sites have also been banned in Nevada.

The companies argue that they are “games of skill” and are therefore exempt from the country’s strict rules on online gambling.

The distinction is irrelevant, Ms Madigan said. As a part of the documents presented Wednesday, she said that illegal gambling occurs in Illinois when a participant “plays a game of chance or skill for money.”