We’re pretty much half way through the 17-week season, and there is only one undefeated team left in the NFL—the defending Super Bowl Champion Green Bay Packers.  Since late in the 2010 season—when there were many Packer fans still calling for Mike McCarthy and Ted Thompson’s heads—Aaron Rodgers & company have been on fire, reeling off 13 straight wins (two to get in the playoffs, four playoff wins, and seven to start this season).

So do the Packers have what it will take to become only the second team to accomplish the perfect 16-0 regular season?  Here’s a breakdown of the rest of their 2011 schedule, looking at how each team could beat the Packers, and why they won’t:

Week 9: at San Diego Chargers

How the Chargers can win: The Packers main weakness on defense has been their pass defense, ranked 31st in the league in yards allowed, which for a team with Philip Rivers, Vincent Jackson, Malcolm Floyd and Antonio Gates would appear to be an area to exploit. Meanwhile, the Chargers defense is ranked 4th overall, thanks to their 4th ranked pass defense. Their 21st ranked rushing defense is an area to exploit, but running the ball isn’t Green Bay’s strength.

Why they won’t win: Unlike many Norv Turner led Charger teams, the 2011 didn’t start slow. But they seem to be hitting a low point right now, losing in overtime to the Chiefs after Rivers fumbled a snap while setting up for a game winning field goal. Their pass defense ranking is helped by games against the Vikings, Dolphins, Chiefs (twice), Broncos and Jets, none of whom surpassed 176 yards through the air – the Vikings managed only 28 yards in the season opener. The only premiere quarterback they’ve faced, Tom Brady, put up over 400 yards.  Stopping Rodgers will be difficult.

Week 10: vs. Minnesota Vikings

How the Vikings can win: Call in a bomb threat and hope the Packers fail to show up only to have the NFL somehow fail to cancel the game?  The Vikings played the Packers tighter than many expected in rookie Christian Ponder’s debut in Week 7.  But that game was in Minnesota.

Why they won’t win: They simply don’t yet have enough talent to hang with the Packers for 60 minutes. They might make it closer than expected again, as Packer/Viking games often are, but only if expectations are 14+ points.

Week 11: vs Tampa Bay Buccaneers

How the Bucs can win: While the Packers pass defense takes a lot of heat, I think it’s the running game that would be the key to victory for the Buccaneers, despite being thin at the position.  One of the reasons the Packers pass defense is rated 31st while their their rush defense is rated 10th (in yards per game) is that many teams end up down so much they have to throw the ball most of the game to catch up. With Josh Freeman regressing in his third season, the Buccaneers need to hope that LaGarratte Blount is healthy enough to again be a workhorse. The Packers are ranked 22nd in yards per carry allowed (4.6) and they gave up 175 yards to Adrian Peterson in Week 7.  If Blount can carry the load, the Bucs can potentially keep Rodgers off the field, and keep themselves in the game.

Why they won’t win: Blount hasn’t been healthy, and hasn’t been as productive as many hoped (including some of us who have him on multiple fantasy leagues), in part due to Freeman—with his struggles, teams are able to commit more guys to the box to stuff the run.  While Blount will be the key, Freeman needs to take some heat off him by being able to hit the occasional pass—something he’s struggled with this year.

Week 12: @ Detroit Lions

How the Lions can win: Early in the season, the Lions were looking like this matchup could actually have NFC North championship implications. The Lions went on a little swoon, though, and have fallen two games back after Week 8.  To have a shot, they need to get healthy—both Matthew Stafford and Jahvid Best need to be at the top of their games to have a shot.  I doubt Best would have an Adrian Peterson-esque day, but Calvin Johnson could eat the Packers defensive backfield up, so all the Lions might need from Best is enough to keep the defense honest against the run.  Also, while he has avoided many hits by getting rid of the ball quickly, some would argue that the Lions defensive line isn’t always worried about whether or not the quarterback has the ball to get their hits in…

Why they won’t win: They need Stafford and Best healthy—neither has a track record of doing so for full seasons.  There’s been rumblings that Best may sit the rest of the season with his concussion issues, and while Stafford has played every game so far and has a bye this week to get healthy, he’s still never played a full season.  And even Ndamukong Suh might not be able to hit Rodgers cleanly, lest he take a $50,000 hit to the pocket book.

Week 13: @ New York Giants

How the Giants can win: The Giants are one of those teams that on any given week the stars can align, everything can go their way, and they can beat anyone in the league.

Why they won’t win: Eli Manning—the Giants are one of those teams that on any given week the stars can align, and even the worst teams in the league can kick the crap out of them.

Week 14: vs Oakland Raiders

How the Raiders can win: Two words: Darren McFadden.  He could run wild on the Packers defense, if he’s healthy.

Why they won’t win: Five words: The Rest Of The Team.  Amazing as it is to say, the Raiders were pretty much screwed as soon as Jason Campbell got hurt—and they’ve mortgaged the future for Carson Palmer, whom I doubt will have improved enough to help them late in the season against the Packers.  Add in a defense that is 25th in the league, and a late season game in Lambeau, and the Raiders will probably need Al Davis looking down on them from above to pull off the win.  Assuming he is actually up above…

Week 15: @ Kansas City Chiefs

How the Chiefs can win: The Chiefs do have an interesting mix of skill players ranging from Dwayne Bowe to Jonathan Baldwin to Jackie Battle to Steve Breaston (and a thing for the letter “B” the way it looks), but at this point, the only way I can see the Chiefs pulling off a win is if Aaron Rodgers becomes so fascinated and enamored with Todd Haley’s scruffy looking beard, that he forgets the Packers playbook.  Assuming Todd Haley still has the beard.

Why they won’t win: If the beard is a true “Victory Beard” and Haley shaves it off after their next loss, it may survive the next two weeks (hosting Miami and Denver), but it would seem unlikely to survive the stretch of four games after that (@ New England, vs. Pittsburgh, @ Chicago, @ NY Jets).

Week 16: vs Chicago Bears

How the Bears can win: Matt Forte has looked better in 2011 than anyone at Zoneblitz ever would have thought possible. Convenient that it’s a contract year, huh? If he’s still performing well in Week 16 and the Bears can get him going, thus taking the ball out of Jay Cutler’s hands, they’ve got a shot.

Why they won’t win: By week 16, Forte’s desire for a new contract, combined with the Bears apparent disinterest in giving him a large deal, may poison his desire to perform big as the season winds down, especially if the Bears are on the outside of the playoff picture.  And let’s not forget that they still have the Cutler factor and an offensive line made up of Lingerie Football League rejects.

Week 17: vs Detroit Lions

How the Lions can win: If the Packers are still undefeated at this point, then they will have locked up the first seed in the playoffs (probably several weeks earlier), and might look at resting several players for significant parts of the game, depending on how Mike McCarthy decides to play it.

Why they won’t win: While the Packers appear to understand that the ultimate goal is a Super Bowl repeat, it doesn’t seem to be in Aaron Rodgers, Clay Matthews, or even Mike McCarthy’s blood to make the safe play and prepare for the playoffs.  Especially if the Lions give them any trouble on Thanksgiving, I would look for the Packers to be out for blood on New Years.

So there you have it—while 10 games in the NFL is an eternity, the Packers have a very realistic shot at going undefeated the rest of the regular season—so then the question starts to become, is there anybody not on their schedule in the NFC that can give them a challenge in the playoffs?