Four teams sit atop the league standings at 10-3: New England, Denver, Arizona and Green Bay. But by no means are they equal. For some insights on how to differentiate a good bet from a great one, we spoke with Ed Feng, founder of The Power Rank . Feng is a math whiz with a Ph.D. in chemical engineering from Stanford, and he founded his site as a quant-driven way for the enlightened sports fan to make money on the game.

After this weekend, there will only be two games left in the NFL regular season. A handful of Super Bowl contenders have emerged, and from now on it's all about seeing which team will make it all the way. Being "good enough" doesn't matter anymore.

"I think Denver is incredibly underrated at this point in the season," Feng said. Despite some betting sites putting the Broncos' Super Bowl odds behind teams like the Patriots, Feng still considers them his favorite. Feng admits "the consensus among power rankings is that the Broncos are at the bottom end of elite teams," but his numbers suggest there's something to be gained by betting on them to win it all. His three main reasons are (1) pass offense, (2) pass defense and (3) the St. Louis game.

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Pass offense: "When I adjust for schedule, Denver's pass offense is better than last year." It's true that on a raw, unadjusted basis, the Broncos' yards-per-pass-attempt is down this year compared with last, but Feng said it's important to consider the change in their schedule. Last year, "they played the woeful NFC East," but this year their games have gotten tougher, putting them up against top pass defenses in Seattle and San Francisco in an NFC West-highlighted schedule.

Pass defense: "By signing Aqib Talib, they have gone from the 16th pass defense last season to second this season. That's a huge improvement." The numbers suggest that the improvement is mostly in the secondary, as "their sack rate hasn't changed much," going from 6.3 percent last year to 6.6 percent this year.

The St. Louis game: Even though the Broncos lost their road game to the Rams 22-7, Denver did out-gain St. Louis in total yards, 397 to 337. Feng said that "Denver only scored seven points because they went 0-2 on fourth down deep in Rams territory, and this was also the game that Emmanuel Sanders got hurt."