Americans are expected to bet an estimated $95 billion on the NFL and college football this season.

Research shows that a legal sports betting market in the United States would be the largest in the world and could potentially generate as much annual revenue as the NFL itself.

A fully developed legal American market -- where bets are placed at casino, online and at retail bookmaking shops -- would produce $12.4 billion in annual revenue.

In comparison, NFL teams shared more than $7.2 billion in league revenue in the 2014 fiscal year.

"Illegal sports betting is reaching new heights of popularity in America," Geoff Freeman, president and CEO of the American Gaming Association, said in the release. "It's clear that a federal ban on traditional sports betting outside of Nevada is failing."

Nevada is the only state allowed under federal law to offer a full menu of sports betting.