Its harness racing industry also opposes the bill, saying its members wouldn't get a fair share of the gambling proceeds.
The bill, which was approved by the House last week, authorizes Delawareans to play slots and table games online. It also expands betting on NFL games to at least 20 more sites other than Delaware's three casinos, and expands the availability of keno to at least 100 sites.
The Markell administration says the gambling expansion would allow the state to eliminate millions of dollars in fees paid by the casinos.