Give it by the end of this year

"Today we have this bizarre situation where it is legal for an American to play online poker for money using a game that is provided by an illegal offshore entity," Loveman said. "I think it is very hard to imagine why we would allow Americans to buy a service that no American company can offer." If the federal government were to legitimize online poker, it would be able to regulate the activity, he added.

But here's the biggest incentive of all: a windfall from taxes. Loveman estimated that under a federally regulated scenario, the U.S. online poker industry could rake in $6 billion to $8 billion a year. If states did this on their own -- and that's looking the most likely -- the revenue would be $2 billion to $3 billion to start.

The federal government would get about 15% of that revenue if it regulated online poker, Loveman estimated.