Although the odds on a spread bet are often listed as being even at 1:1, the fact is they are 0.90:1, which is a bit less than even. How does this work? Often in the point spread you’ll see next to each spread number -110. This tells you how much you have to wager to make $100. Thus, with the point spread -100 will always be listed, which means if someone wagers $110, they will make a $100 profit if they win. (If betting $11.00, the payout would be $10.00)
Placing a point spread bet means gambling on how much a team will win or lose by. In our above example, the Cowboys are the favorite. How do we know that? The minus symbol in front of the point spread indicates that the bookmaker thinks the final score will have Dallas winning by 7.5 points or more. The underdog, in our example that’s the New York Giants, will always be indicated with a plus sign. If you wager on the Cowboys on the point spread, America’s Team will have to win by at least 8 points for your wager to pay off. Should the Cowboys win by less than 8 points, your bet is lost.

In June 2017, the Supreme Court of the United States announced that it would hear New Jersey's case, Murphy v. National Collegiate Athletic Association, in the fall of 2017, contradicting the position of the US Acting Solicitor General, Jeffrey Wall, who asked that the case not be heard in May 2017.[18] In September 2017, a poll conducted by the Washington Post and the University of Massachusetts Lowell shows 55% majority of adults in the U.S. approve of legalizing betting on pro sporting events.[19]
Point Spread: The point spread remains the favorite way to wager on pro football, regardless of how many new forms of wagering come on stream. It’s called the line or spread and it’s known as betting ‘sides.’ The common misconception is that Las Vegas sets the spread as its best guess at the margin of victory. But really, it's a number they feel that is a perfect balance and will see an equal number of people to bet the underdog as on the favorite. A negative value like -6.5 means that team is favored by 6.5 points. So deduct 6.5 points from their total score. A positive value on the same game would be +6.5 (add 6.5 points to their final score) and would make that team an underdog of 6.5 points. The favorite must win by at least seven points to cover the spread. The underdog can lose by six points and still cover.