Bookies, beware: The Patriots are king of the spread

For gamblers who have consistently bet on the New England Patriots this year, Christmas has come nearly every Sunday.

Last weekend’s victory against the Denver Broncos gave the Patriots a 12-2 win-loss record for the season, and lifted their record against the point spread to an NFL-best 11-3, exceeding the projections of bookmakers more times than any other team in the league. That means — for nongamblers or the gambling-curious — that if the Patriots were favored in a given game by, let’s say 6 points, they would have to win by 7 or more to beat the spread.

“Pats minus-3 at Denver? I was dancing,” said one joyful Massachusetts sports gambler and bookmaker, referring to last Sunday’s point spread, which the Pats covered with ease by winning 16-3. He padded his account with a winning bet on the Patriots.

For more than a decade, New England’s team has mostly had its way with the NFL on the field, while also topping the league with those even tougher competitors in Las Vegas: the odds makers.

Since 2003, the Patriots not only have beaten the spread more often than any other NFL squad, but the average number of points by which they cover — 3.6 — is significantly higher than any other team, said Tom Federico, cofounder and chief executive of the sports analytics website Teamrankings.com, and one of the site’s self-described stat nerds.

With a nearly 14-year sample of roughly 250 games including playoffs, the numbers suggest “the Patriots are absolutely an outlier” when it comes to exceeding Las Vegas’ expectations, Federico said.

“You look at these things in retrospect and see if you want to have been an amazingly successful sports bettor, all you need to do is bet the Patriots every single week,” he said. “Just blind-bet the Patriots.”

As they say in investing, past performance does not guarantee future results. But this year, New England has covered 78.6 percent of point spreads, which would be the fourth-best percentage for any NFL team in a season dating back to at least 2003, according to numbers compiled by Teamrankings.com. One great year against the spread is merely a curiosity to the math nerds. Consider the 2004 San Diego Chargers, a decent but unmemorable team that somehow became the ’85 Bears of the point spread, by covering 86.7 percent of the time. That Chargers team went 12-4 on the field and lost in the first round of the playoffs.

For sports gambling novices — those who have never screamed at the ceiling over an underdog’s garbage-time touchdown — the point spread is a tool used by bookies or sportsbooks to encourage roughly equal wagers on both teams in a particular game.

Take, for instance, the Patriots’ matchup this week against the New York Jets. The Pats appear to be rounding into peak form. The Jets started slowly this season, and have tapered off. At 4-10, they have one of the league’s worst records, their lead running back has an injured knee, and the team played last week like it was looking forward to vacation.

So who would ever bet on the Jets? And if everybody bet on the likely winner, how could the casino stay in business?

That’s why Las Vegas, ever the temptress, is trying to attract money to the Jets through the point spread.

The opening spread for this Sunday’s game was an enormous 14 points at the Caesars Palace sports book in Las Vegas, according to Frank Kunovic, director of the Caesars Entertainment Race & Sportsbook. That betting line was set by Caesars’ team of in-house expert oddsmakers.

Meaning, if you risk money on the underdog Jets, you will win not only if New York wins the game but even if the team barely manages to avoid getting stomped by two touchdowns. If you want to bet on the favored Pats, you need them to not only win the game, but to win by more than 14.

Other oddsmakers had the opening line as large as 16.5 points, the largest opening spread in three years, according to CBS Sports.

With a point spread so large, the Jets are maybe not such a crazy wager.

“The goal for bookmaking is to have an even amount of money on both sides of the game,” Kunovic said. Casinos keep a small slice of the action on each bet, so the house is guaranteed to make money if an equal amount of cash is bet on each side.

Sportsbooks will sometimes allow the bets to be unbalanced when they think they have an advantage, said Federico. “They’re pretty advanced in knowing what’s sharp action and what’s dumb action,” he said. “They’ll let the [bets] get imbalanced in certain cases when they think it’s just a bunch of dumb money accumulating on one side.” For example, back when the Los Angeles Lakers were great, the lines were “artificially inflated” and “you’d get all these square bettors from LA driving to Vegas and no matter what the line, they’d bet the Lakers to cover,” he said.

Once the initial line is set, the house may move the line toward one team or the other, depending on how the money comes in. Despite Caesars’ 14-point opening line in the Pats-Jets game, most initial bets were still on the Patriots, Kunovic said. Caesars moved the line for new wagers to 16.5 points, to entice more bets on New York.

It may still not be enough to even out the money. The sports betting analytics website SportsInsights.com tracks data from seven online sportsbooks. Last week, 78 percent of the bets placed in the Patriots-Broncos game were placed on the Pats, said the site’s president, Daniel Fabrizio, by e-mail. “It’s very rare for the majority of bettors to not bet the Pats.”

Since 2003, New England has failed to receive a majority of the bets in just 30 games, he said, and in those games the Pats have punished those of little faith by going an insane 23-7. Two of those games were this year; in Week 1, when quarterback Tom Brady began his four-game suspension, and Week 3, when No. 2 quarterback Jimmy Garoppolo could not play due to an injury, he said. The Pats covered both times.

“Every time [the Patriots] cover, Vegas hurts a little,” Kunovic said. “They keep covering and because they’re such a popular team, we’ve been losing money on them all season.”

This may be a good time to mention that sports gambling is illegal in Massachusetts, despite how widely practiced it seems to be. The attorney general’s office last year charged 33 people in a 122-count indictment related to an alleged sports betting enterprise in Boston and the South Shore. Such high-profile arrests may not deter gambling, but they do seem to have a chilling effect on getting gamblers to speak on the record. Bettors in this story spoke only on the condition of anonymity because they would prefer not to be arrested.

Local bookies know the stats as well as anybody, and have adjusted to the Patriots’ success and popularity. The Patriots were 3-point favorites last weekend nationally, “but locally I know a lot of bookies had them at five because everyone locally takes them,” said one gambler and bookmaker. He said he does not accept bets on New England. “It’s basically giving money away,” he said.

Vegas has also tried to compensate. “We keep putting the line more and more toward the Patriots, making them a bigger favorite to try and attract more money on the other side,” said Kunovic, of Caesars. “But the line just never seems to be enough.”

“We’re pretty good at making money here in Vegas,” he said, “but the Patriots have made that fairly tough recently.”

Mark Arsenault can be reached at mark.arsenault@globe.com. Follow him on Twitter @bostonglobemark.