The presumptive favorites to reach Super Bowl XLIV are obvious.
For another, there are other contenders that haven't won as many games, but have demonstrated they have what it takes to be a force in the playoffs.
San Diego Chargers (10-3)
1. Eight-game winning streak. The Chargers are as hot as any team in the NFL, including the Saints and Colts. They've passed multiple big tests, including a 32-3 blowout of the Broncos at Denver on Nov. 22 and last Sunday's 20-17 win at Dallas. A Week 15 victory against Cincinnati would put them in good shape to capture the No. 2 seed in the AFC playoffs.
2. Quarterback Philip Rivers. He's playing as well as he has at any point of his career, making him a legitimate candidate for league MVP honors. Not only has Rivers been highly productive, but he also has proven to be very efficient and should have no problem taking good care of the football in the pressure cooker that is the postseason.
3. Tight end Antonio Gates, wide receiver Vincent Jackson, and running backs LaDainian Tomlinson and Darren Sproles. This might very well be the most dangerous foursome of playmakers in the NFL. Rivers knows how to make the most of them in the passing game, and, although the Chargers rank near the bottom of the league in rushing, Tomlinson and Sproles still command enough respect for their running skills to keep defenses honest.
4. Defense. The Chargers' aggressive scheme allows them to generate strong pressure on the quarterback. They also do a solid job against the run.
5. Last January's wild-card victory over the Colts. The Chargers' defense had no trouble keeping Peyton Manning and the Colts' explosive passing game under control. Although the game was in San Diego, the Chargers have shown this season they're capable of performing as well on the road as they do at home.
Minnesota Vikings (11-2)
1. Winning five of their last six games. The only loss, at Arizona in Week 13, did raise some questions about the Vikings' worthiness as a serious Super Bowl contender. It was a rare instance when an opponent was more physical, and rare is the operative word. The Vikings quickly shook off their worst performance of the season by pounding the Bengals a week later.
2. Defense. The Vikings have one of the NFL's best pass rushers in end Jared Allen, who thrives from the fact that their fearsome tackle duo of Pat and Kevin Williams routinely owns the middle. The return of cornerback Antoine Winfield from a broken foot enhances an already strong secondary.
3. Quarterback Brett Favre. He came out of retirement to give the Vikings' passing game the big-play dimension that it has lacked, and that is exactly what he has done. He's playing the best football of his long and illustrious career, putting himself in the thick of the MVP race. With Favre, the Vikings have become a more pass-oriented offense that pressures opponents with a quick-striking attack.
4. Running backs Adrian Peterson and Chester Taylor. Even with Favre under center, the Vikings still have one of the very best running backs in the league in Peterson. He can take control of a game at any time, especially with opponents forced to respect the explosiveness of the Vikings' passing attack. Taylor also is extremely effective, giving the Vikes an outstanding one-two punch on the ground.
5. Wide receivers Percy Harvin and Sidney Rice. Harvin's chronic migraines are a concern, but when he's healthy, he is an ultra-dangerous receiver, which is why he is the favorite for offensive rookie of the year honors. Favre has helped turn Rice into one of the NFL's premier game-breakers.
Philadelphia Eagles (9-4)
1. Four-game winning streak. After a lopsided loss to the Chargers, the Eagles have caught fire. Their offense has been highly explosive, scoring 27 or more points in the last three games. And they've done this despite being without running back Brian Westbrook, who has been sidelined with a concussion. The Eagles' last two wins, against Atlanta and the New York Giants, have been especially impressive.
2. Wide receiver DeSean Jackson. He has emerged as one of the most dynamic offensive players in the league. He has tied an NFL record with eight touchdowns of 50 or more yards this season.
3. Quarterback Donovan McNabb. He might not be playing as well as Peyton Manning, Drew Brees, Brett Favre or Philip Rivers, but he still is among the better passers in the league and knows his way around the postseason.
4. Defense. As they demonstrated against the Giants in Week 14, the Eagles can give up a lot of points quickly, but a good deal of that results from a quick-striking offense that doesn't give the defense a whole lot of time to rest. But the Eagles are stout up front; they haven't allowed a 100-yard rusher in 23 consecutive games, dating back to last season. They're also capable of applying plenty of pressure on the quarterback with a wide variety of blitzes and coverage disguises/combinations that often force the quarterback to hold the ball too long.
5. Getting healthy at the right time. Westbrook could be coming back soon from concussions that caused him to miss five of his last six games, although it probably won't be Sunday against San Francisco, as originally expected. Kevin Curtis, the Eagles' last 1,000-yard receiver, is returning from a knee injury.
Green Bay Packers (9-4)
1. Five-game winning streak. Since their stunning Week 9 loss to Tampa Bay, the Packers have been on a serious roll. The two best teams they've beaten in that stretch are Dallas and Baltimore.
2. Quarterback Aaron Rodgers. He has put up impressive enough numbers to at least reside on the fringes of the MVP discussion.
3. Defense. Despite season-ending injuries to two of its best players, cornerback Al Harris and outside linebacker Aaron Kampman, the unit has made a remarkably successful transition from a 4-3 to a 3-4 scheme under new coordinator Dom Capers. The Packers rank second in the league in overall defense, second against the run, and third against the pass.
4. Wide receivers Greg Jennings and Donald Driver, and tight end Jermichael Finley. The Packers' multiple playmakers have had plenty to do with Rodgers' success. Finley, who has a great deal of speed and athleticism, is steadily growing into a more important role in the Packers' offense. His increasing effectiveness as a target over the middle creates a coverage dilemma as opponents weigh that against the need to double Jennings and/or Driver outside.
5. Running back Ryan Grant. The Packers' running game is solid, ranking 13th in the NFL. Despite lacking consistency, it has demonstrated that it can rise to the occasion during crunch time, as Grant demonstrated by averaging a season-high 6.9 yards per carry last week against Chicago while Rodgers was throwing for a season-low 180 yards.
Arizona Cardinals (8-5)
1. Winning four of their last six games. The seven-turnover disaster at San Francisco on Monday night was embarrassing, but not the end of the world. The Cardinals lost their focus but remain a highly-talented team with one of the most explosive offenses in the league. Their Week 13 triumph over the Vikings made a loud statement that they belong among the league's elite.
2. Quarterback Kurt Warner and wide receivers Larry Fitzgerald and Anquan Boldin. This continues to be one of the most dangerous passing-game trios in the league. Warner has dealt with a concussion, but looks as if he'll be OK, despite the poor showing that he and the rest of the Cardinals' offense had against the 49ers. Fitzgerald looks as if he'll be back this week from the knee injury that caused him to miss part of the San Francisco game.
3. Turning red hot in last season's playoffs. The Cardinals have ample reason to believe they can compete at the highest level when it counts, because that was exactly what they did last year, overcoming losses in four of their final six regular-season games to make an amazing run all the way to Super Bowl XLIII. On top of that, they feel they have something to prove to the many doubters who -- despite watching the Cardinals push Pittsburgh to the limit in that game -- might still question their playoff worthiness.
4. Defensive end Darnell Dockett. His combination of power and quickness make him a game-changing force who consistently draws multiple blockers.
5. Cornerback Dominique Rodgers-Cromartie. His speed and excellent coverage skills allow him to match up well against every opponent's top receiver.