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When you think about it, the NFL doesn't offer many surprises as we trudge along each season. That is, not when it comes to division titles and postseason berths.

Sure, we get feel-good stories and worst-to-first elation from time to time. No two seasons are the same, and the balance of power shifts over time. By and large, however, we see many of the same teams in contention each year.

Think about it. Which teams are considered perennial postseason locks? The New England Patriots, Denver Broncos, Indianapolis Colts, Pittsburgh Steelers, Green Bay Packers and Seattle Seahawks are virtually in before the season begins, even with offseason drama and attrition. The Philadelphia Eagles, Baltimore Ravens, Cincinnati Bengals and Arizona Cardinals come close.

Of course, the phrase "Any Given Sunday" exists for a reason. The injury bogeyman lurks around every corner, and Father Time stalks even the best players. But, again, we are talking about year-to-year.

What's the point of this rambling preamble? All of it was to say few teams make the leap from bad or mediocre to playoff powerhouse in one year.

So which team is going to do it in 2015? That would be the Minnesota Vikings, though this is hardly a new or shocking notion. Sports Illustrated's Chris Burke and NFL.com's Chris Trapasso shared tweets regarding the Vikings' contending potential:

Are the Vikings a sleeper in the NFC North? Or does everyone calling them a sleeper mean that they are not really a sleeper? — Chris Burke (@ChrisBurke_SI) August 18, 2015

If #Vikings OL comes around, I think they can contend w/ #Packers for NFC North title. IMO, Minnesota is definitely a wild card-caliber club — Chris Trapasso (@ChrisTrapasso) July 14, 2015

Why do so many think the Vikings are sleepers to wrest the NFC North crown from the Packers? Well, a few reasons come to mind.

The Head Coach

Why did it take so long for Mike Zimmer to get a head coaching gig? The overarching theory had been his bristling personality became problematic during the interview process, as written by Mark Craig of the Star Tribune:

Yet Zimmer was consistently passed over for head coaching jobs. One person close to him said it’s probably because Zimmer is too frank, too unpolished and that, “he’s made his mark as a football coach, not a smooth, slick CEO who walks in with his own PR firm.” Zimmer told reporters in Cincinnati two weeks ago that he’s gotten better at interviewing since admittedly blowing one with the Rams years ago. He also said there were times when he knew immediately that the fit wasn’t right.

Good thing the Vikings got past all that.

Zimmer is no Bill Belichick—at least not until he goes to the Super Bowl six times in the next 15 years—but he is an improvement on the coaches of yesteryear in Minnesota. That much was evident in just one season, when the Vikings had a surprising 7-9 record and hung in there against several good teams.

His deft navigation through the Adrian Peterson saga as a rookie head coach was a testament to his leadership ability. His ability to navigate the team to an improved season under a rookie quarterback showed he was the right man for the job.

The fiery head coach's impassioned personality is a stark difference to his predecessor's, perhaps stoking the competitive flames in Minnesota. That and he's been a pretty good defensive coach for years. Speaking of which, that unit is going to make or break the Vikings' postseason hopes in 2015.

The Defense

Quietly—and not surprisingly, given head coach Mike Zimmer's defensive mentality—the Vikings have put together a young, solid defense capable of great things.

The Vikings ranked 11th in scoring defense and 14th in total defense last season. Those aren't particularly gaudy rankings, but they represent quite an improvement over the previous season. Minnesota ranked dead last in scoring and gave up the second-most total yards.

Headlined by youngsters such as safety Harrison Smith—one of the league's best safeties—defensive tackle Sharrif Floyd and linebacker Anthony Barr, that unit is poised for a huge season. They are joined by rookies Trae Waynes, Eric Kendricks and Danielle Hunter, whom the Vikings took in the first three rounds of the draft.

Waynes has gotten toasted all preseason long, but he has some veterans such as Xavier Rhodes, Terence Newman and Captain Munnerlyn ahead of him while he learns. Kendricks, meanwhile, looks every bit like a first-round talent that fell into the second.

That defensive line anchored by Floyd and Linval Joseph and flanked by up-and-coming pass-rusher Everson Griffen, who eclipsed double-digit sacks last season and ranked eighth among all 4-3 defensive ends, according to Pro Football Focus.

Plainly put, the Vikings are loaded with good, young talent on the defensive side of the ball, and they have the coaching staff to get that unit to the top of the league. That's bad news for the rest of the division.

The Quarterback

You don't need a great quarterback to win. But playoff contenders tend to have one.

Other than a fleeting time with Brett Favre that seems like a past dream at this point, the Vikings haven't had much luck at quarterback over the past decade. That is no longer the case.

Somehow Teddy Bridgewater nearly fell all the way out of the first round a year ago. Rick Spielman had the presence of mind to trade back into the round to snag him before another quarterback-starved team could. It was possibly the best decision he's ever made in Minnesota, though passing on Bridgewater earlier could have been disastrous.

Of course, we are getting ahead of ourselves. Bridgewater may turn out to be the next coming of Randall Cunningham, or he could bust out of the league. The odds are in his favor after what we saw as a rookie.

Bridgewater was one of five rookie quarterbacks in NFL history having thrown more than five touchdowns who completed over 60 percent of his passes for over seven yards per attempt, according to Pro-Football-Reference.com. More important than numbers, he looked the part—Bridgewater was one of PFF's top-rated quarterbacks during the season's second half.

With one year under his belt, the sophomore out of Louisville is poised for a great second season. It won't be merely on talent, either.

The Supporting Cast

He may be 30 years old and a year removed from the game, but Adrian Peterson has defied the odds before.

The former MVP is back with a vengeance after his year from hell. The merits of reinstating him aside, he is going to balance that offense like Jerick McKinnon and Matt Asiata couldn't last season. This is the same running back who rushed for 2,000 yards while dragging Christian Ponder and Co. into the playoffs just three years ago.

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He rejoins a team with budding talent all around. Charles Johnson broke out late last season after bouncing around as a rookie. Kyle Rudolph is a bundle of promise that has either been miscast or injured in his first four years in the league.

If he can stay healthy in offensive coordinator Norv Turner's tight end-friendly offense, he is in for a big year.

Minnesota also went out and got a bona fide deep threat in Mike Wallace. Burned bridges and consistency issues notwithstanding, Wallace is still an effective receiver who scored double-digit touchdowns last season. If he can strike up a deep-ball rapport with Bridgewater, that offense will utterly bedevil opposing defenses.

Stop the run? Bracket Wallace? Clamp down on Rudolph? Pick your poison.

The End

Winning the NFC North will be no easy task, though the Vikings won't have to do that to make the playoffs. The ever-powerful Green Bay Packers figure to take the crown after narrowly missing out on a Super Bowl berth, and the Detroit Lions are going to be a tough out yet again.

(Apologies to Chicago Bears fans, but you know it's not happening.)

The roster certainly has holes in it, too, particularly on the offensive line. The cornerback position is unsettled, too, unless Waynes can make a dramatic turnaround in the coming weeks.

But what team is without warts? Even the great Seahawks have issues on the offensive line. The Vikings have the pieces elsewhere to overcome deficiencies and shock the NFL world this fall.

Follow @AlexMiglio