Parity has long been one of the NFL's calling cards and a major reason it continues a runaway as the country's most popular sports league.

Sure, it's been largely dominated by the New England Patriots for the past two decades, but rarely has the greatest dynasty in NFL history been viewed as a prohibitive favorite. And hope springs eternal league-wide because the draft, salary cap, injuries and a limited inventory of games combine to provide just about any club the opportunity to make a deep playoff surge.

Who saw the Tennessee Titans reaching the championship round last season? Or the Jacksonville Jaguars in 2017? Heck, the more time passes, the more remarkable the Atlanta Falcons' run to Super Bowl LI – and overtime fail at New England's hands – seems.

The NFL loves to cite year-over-year turnover in its playoff field. Since 1990, when the 12-team postseason format was implemented, at least four new teams (and often many more) have reached the Super Bowl tournament annually after being spectators the previous year. 

But it's more than a churn of predictable powers. Since 2015, 29 of the league's 32 teams have made at least one playoff trip. Since 2010, when the New York Jets reached the second of two consecutive AFC championship games, the only teams absent from postseason are the Buccaneers (last appearance, 2007) and Browns (2002) – two organizations that could very well cast futility aside in 2020.

And, don't forget, we're guaranteed at least two new playoff entries this season with the league expanding to a 14-team bracket for the first time in a non-strike campaign.

Here are nine that seem likeliest to break through, from most likely to least, with September's action now in the books (current record in parentheses):

1. Pittsburgh Steelers (3-0): Baltimore's loss Monday gave Pittsburgh sole possession of first place in the AFC North, though the Steelers will have to contend with both the Browns and Ravens in October. But every reason to be upbeat about a team that seems to be wedding last year's dominant defense with an offense once again thriving under QB Ben Roethlisberger's watch. Big Ben is playing at a high level, his 105.2 passer rating on track to establish a career high, and the rejuvenation of his elbow coinciding with renaissance seasons from RB James Conner and WR JuJu Smith-Schuster. More important, that elite D ranks second (290 yards allowed per game) and is once again leading the NFL in sacks (15). Whether or not the Steelers knock Baltimore from the divisional throne, Pittsburgh looks capable of making serious noise in January.

2. Tampa Bay Buccaneers (2-1): Despite their season-opening loss at New Orleans, the Bucs have bounced back to claim exclusive ownership of first place in the NFC South. QB Tom Brady's play has steadily improved (yes, his opponents have also gotten steadily worse), former Pats teammate Rob Gronkowski returned to relevance Sunday in Denver, and key rookies like RT Tristan Wirfs and S Antoine Winfield Jr. are playing well.