Experts said one advantage New Jersey has that not all states could leverage is a large population and economy.
"When you look at smaller states and you look at games such as poker, you need liquidity for those games to work," said Geoff Freeman, president and CEO of the American Gaming Association (AGA). "In states like Nevada and Delaware, that liquidity may not be there at this point in time."
Figures for the entire 2013 fiscal year for Delaware's gaming industry have not been released, but casino slot revenue was down more than 47 million in the first five months of 2013 compared to 2012.
Not all of the gaming industry's heavyweights are endorsing the Internet migration. Sheldon Adelson, chairman and CEO of Las Vegas Sands Corp., has been outspoken about his moral objections to online gambling. "'Click your mouse and lose your house' isn't a marketing slogan for advocates of legalized online gambling. But it should be," he wrote in Forbes earlier this year.
When the slot machine was new
Many gaming experts believe online gambling will prove to be profitable in the long run.
"If you were looking at monthly numbers trying to gauge the potential of slot machines in, say, 1965, you'd be at a loss, but ultimately that new technology had a big impact," Schwartz said.
Caesars Entertainment Corp., the largest casino company in the world, spun off its online gaming ventures as a separate publicly traded company, Caesars Acquisition, in November. This move was in conjunction with existing private equity partners Apollo Global Management and TPG Capital.
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"My guess is that online gambling will continue to expand and most states will approve it and it will continue to grow," Dunkelberg said. "Online gambling will increase the total volume of gambling revenues that happens, because people who want the ambiance will still fly to Vegas and go to Atlantic City or go to some casino in Philadelphia," he said.
And there may be a better early indicator of online gambling's potential than New Jersey's initial numbers. Internet gaming thrived on the black market after Congress passed the Unlawful Internet Gambling Enforcement Act of 2006, which made illegal any transactions between banks and online gambling sites. This ability to thrive—while illegal—revealed the industry's potential for revenue growth and has influenced not only states to pursue legalization but also, ironically, the federal government, which had initially banned it.
"The demand is there," Freeman said. "Americans spent about 3 billion dollars in online gaming in 2012 before it was even legal in the United States. That 3 billion was going to illegal offshore operators."
Because online gambling is an interstate commerce, like most Internet businesses, federal regulation is seen by some as an even better alternative than a state-by-state approach to regulation. One bill, introduced by Representative Peter King, R-N.Y., would legalize all forms of online gambling (except sports), create an oversight office at the Treasury Department and allow states to opt out.
Another bill, introduced by Representative Jim McDermott (D-WA), proposes a 4 percent federal tax on operators, and allows states to collect an additional 8 percent.
"It's not that I support or oppose Internet gambling; it's that I understand human nature," Congressman McDermott said in an email statement provided by a spokesperson. "Online gambling isn't going away, so we might as well make it safe and try to raise funds for programs that the public wants and needs."
The AGA argued that federal action would also curb illegal offshore Internet gaming sites. More states, and even the federal government, are beginning to see the potential of drawing consumers and the billions spent in illegal online gambling toward licensed and taxed domestic operators as a benefit that far outweighs the more immediate growing pains of developing a successful model for Internet betting in the U.S.
"I think online gambling is the next generation for gaming in America. In all products that we see in our society—whether books, music or other things that people enjoy—you have to adapt to the Internet," Freeman said.