The 2015 NFL season kicks off tomorrow night when the New England Patriots host the Pittsburgh Steelers at 8:30 p.m. Sports wagering in the United States will also "officially" begin, as football season is the most popular time to place bets.

For some perspective, the American Gaming Association estimated in a news release prior to Super Bowl XLIX that $3.8 billion in illegal sports bets would be placed on the final game of the NFL season, which was said to be 38 times greater than bets wagered legally.

Here's how much the AGA expects sports fans in the U.S. to wager on football games this year:

"The American Gaming Association (AGA) is estimating that sports fans will wager $95 billion on NFL and college football games this season," the association said in a press release. "The vast majority - $93 billion - of wagers will be placed illegally. Just under $2 billion will be wagered at sports books in Nevada."

Sports betting has reached new heights in the U.S. in recent years. However, despite the growing market, the federal government has refused to legalize sports wagering outside the states where the 1992 Professional and Amateur Sports Protection Act permits it. The AGA, among other proponents of legalized betting, believes the federal government needs to repeal the 1992 act because the burgeoning market is facilitating the growth of criminal networks that use the market to their advantage.

"America's sports gambling prohibition has created what many consider (these things are difficult to measure) the world's largest black market for sports betting," Will Hobson of the Washington Post wrote earlier this year. "While nearly $4 billion is bet on sports legally in Las Vegas yearly, an estimated $80 billion to $380 billion is wagered illegally through a shadow industry of offshore online betting houses, office pools and neighborhood bookmakers. Legal or not, the money continues to flow, and a growing number of power brokers advocate legalization so government can tax those billions and sports leagues can track it for signs of corruption."

The AGA formed a Sports Betting Task Force earlier this year to study the issue of sports betting, and the association expects that group to make a formal recommendation on the industry's position later this fall.

"Illegal sports betting is one of four key illegal gambling areas of focus as part of the AGA's 'Stop Illegal Gambling - Play it Safe' initiative, which seeks to distinguish the highly regulated, $240 billion legal gaming industry-which supports 1.7 million jobs and generates $38 billion in taxes across 40 states-from the criminal networks that rely on illegal gambling to fund violent crimes and drug and human trafficking. The initiative is also focusing on black market machines, Internet sweepstakes cafes and illegal online betting," the association noted in the same press release.

New Jersey has been at the forefront of this argument. The state has been attempting to legalize sports wagering at its casinos and racetracks, but the five major sports leagues (NFL, MLB, NBA, NHL and NCAA) have prevented that from happening by filing a suit back in 2014, citing the 1992 act as their defense.

Two separate panels of federal judges ruled in favor of the five major sports leagues, and New Jersey has failed to legalize sports betting to date.

However, increasing pressure from states could change the status quo. Six states have introduced sports betting bills in 2015 alone. New York, Indiana, Minnesota, Mississippi, South Carolina and Texas have joined New Jersey in an attempt to legalize sports betting outside of Nevada, Oregon, Montana and Delaware.

Additionally, NBA Commissioner Adam Silver and MLB Commissioner Rob Manfred have both expressed openness to the idea of cooperating with the government to legalize sports wagering throughout the United States.

However, it will remain illegal in 2015, and that seemingly won't stop anyone from placing their bets.