Who will lay claim to 2016 World Series title?

The 2015 season is over, which means -- because it's always baseball season -- it's time to start looking ahead to the '16 campaign.

The World Series champion Kansas City Royals are set defend their crown for the first time in 30 years, and they'll face some stiff competition in 2016. This past season saw a number of supremely talented young clubs make the next step toward contention. They figure to be back next year, as do a few perennial contenders.

With that in mind, let's take a look at the World Series favorites, heading into the 2016 season:

Perennial contenders

Kansas City Royals

Video: MLB Tonight on if the Royals are a new dynasty

2015: 95-67, won World Series

Key free agents: Johnny Cueto, Ben Zobrist, Alex Rios

Why they could win: If you watched the Royals over the past month, you know they're capable of pretty much anything -- including a repeat. The 2015 Royals were one of the deepest teams in recent memory, and they return an impressive core that includes Lorenzo Cain, Eric Hosmer, Mike Moustakas, Salvador Perez, Alcides Escobar, Yordano Ventura and Wade Davis.

Offseason questions: The Royals face the same questions they faced in July before bringing in Cueto and Zobrist at the Trade Deadline. They could use a front-line starter, and they could use a second baseman/right fielder. Left fielder Alex Gordon also has a $12.5 million player option.

St. Louis Cardinals

Video: GM Mozeliak, Matheny wrap 2015 season, look to 2016

2015: 100-62, Lost in NLDS

Key free agents: Jason Heyward, John Lackey

Why they could win: As an organization, the Cardinals are a well-oiled machine, consistently churning out big league-caliber talent. The potential loss of Heyward could be mitigated by Stephen Piscotty and Randal Grichuk in the outfield. Plus, if Adam Wainwright and Carlos Martinez are healthy, the Cards will boast one of the most fearsome rotations in baseball.

Offseason questions: Martinez's health is the biggest issue. But the Cardinals must also decide whether they'd like to bring back Heyward and Lackey -- and if they don't, how they'd like to replace them.

Pittsburgh Pirates

2015: 98-64, lost in NL Wild Card Game

Key free agents: A.J. Burnett (retiring), Aramis Ramirez (retiring), J.A. Happ

Why they could win: Andrew McCutchen and Gerrit Cole, who are among the game's brightest stars, return. Plus, Pittsburgh boasts what figures to be one of the game's best outfields for years to come -- both offensively and defensively -- with Starling Marte and Gregory Polanco joining Cutch.

Offseason questions: One of the Pirates' strengths as an organization has been their uncanny knack for building a deep rotation. This offseason could present a few hurdles with Burnett and Happ set to depart. Prospects Tyler Glasnow and Jameson Taillon should have bright futures ahead of them, but the Bucs might be best served to add another veteran arm.

Los Angeles Dodgers

Video: Steve Sax on the Dodgers' plans for 2016

2015: 92-70, lost in NLDS

Key free agents: Zack Greinke, Brett Anderson, Jimmy Rollins, Howie Kendrick

Why they could win: The Dodgers have the best pitcher of his generation in Clayton Kershaw and the cash flow to surround him with talent. In Corey Seager and Joc Pederson, Los Angeles has some very skilled youngsters sprinkled into an already quality offense.

Offseason questions: Greinke, Greinke, Greinke. The Cy Young candidate opted out of his contract, and he'll be one of the game's most sought-after arms over the next few months. If the Dodgers can't re-sign Greinke, they'd almost certainly need to make a run at another front-line starter (David Price?) to back up Kershaw. Plus, Brett Anderson is set to leave as well, and the Dodgers are uncertain what to expect from Brandon McCarthy (Tommy John surgery) and Hyun-jin Ryu (shoulder surgery).

Young and hungry

New York Mets

2015: 90-72, lost in World Series

Key free agents: Yoenis Cespedes, Daniel Murphy, Bartolo Colon, Tyler Clippard

Why they could win: The Mets have enough young, controllable pitching talent to make them contenders for years to come. Matt Harvey, Jacob deGrom, Noah Syndergaard and Steven Matz comprise one of the most formidable rotations in the Majors -- not to mention Zack Wheeler, who should be set to return from Tommy John surgery.

Offseason questions: The potential losses of Cespedes and Murphy pose the biggest threat to the Mets' chances of repeating in the NL East. They have in-house options -- Michael Conforto and Dilson Herrera -- for replacing those two, but may choose to look externally for some offensive help as well.

Houston Astros 2015: 86-76, lost ALDS

Key free agents: Colby Rasmus, Scott Kazmir

Why they could win: The Astros were decidedly ahead of schedule when they made their playoff run this year. Now, one of the youngest ballclubs in the league also has some pivotal playoff experience under its belt. Shortstop Carlos Correa is a superstar-in-the-making, and left-hander Dallas Keuchel has become a bona fide ace. Plus, Jose Altuve, George Springer and Lance McCullers offer star power -- all at 26 years old or younger.

Offseason questions: The Astros' bullpen certainly wasn't a weakness, but it wouldn't hurt if they decided to shore it up. Houston can replace Rasmus with its young outfield talent, but the loss of Kazmir leaves a bit of a void behind Keuchel in the rotation.

Chicago Cubs 2015: 97-65, lost NLCS

Video: NLCS Gm4: Maddon looks ahead to Cubs' 2016 season

Key free agents: Dexter Fowler

Why they could win: No one has more young talent among position players than the Cubs, with Kris Bryant, Anthony Rizzo, Kyle Schwarber, Addison Russell, Javier Baez and Jorge Soler. Plus, Jake Arrieta and Jon Lester headline a formidable starting rotation.

Offseason questions: The Cubs will need to replace Fowler in center field, and they could use more rotation help behind their big two. Hector Rondon has evolved into a reliable closer, but the Cubs also need to address the rest of their bullpen and how to bridge the gap to Rondon.

Texas Rangers 2015: 88-74, lost in ALDS

Key free agents: Yovani Gallardo, Colby Lewis, Mike Napoli

Why they could win: If Yu Darvish returns from Tommy John surgery, he'll pair with Cole Hamels to make up the toughest 1-2 punch in the AL. Plus, Texas' offense will still be potent, especially with the development of Rougned Odor and Joey Gallo.

Offseason questions: Just how ready are starters Nick Martinez, Martin Perez and Chi Chi Gonzalez -- all 25 years old or younger -- to shine every fifth day for an entire season? Plus, Adrian Beltre will turn 37 during Opening Week, and the Rangers have five players in their potential Opening Day lineup older than 30.

Maybe by March ...

These teams could join the list of favorites by making the right moves in the offseason.

Washington Nationals

2015: 83-79, missed postseason

Key free agents: Jordan Zimmermann, Doug Fister, Ian Desmond, Denard Span

Why they could win: The Nationals might have the best building block in all of baseball in right fielder Bryce Harper, who posted one of the greatest age-22 seasons ever. Max Scherzer, Stephen Strasburg and Gio Gonzalez all return to the rotation.

Offseason questions: Youngsters Joe Ross (RHP), Michael Taylor (CF) and Trea Turner (SS) could fill the voids left by free agency. But the Nats could use another starting pitcher. Plus, there's the situation with Jonathan Papelbon, who has another year left on his contract.

New York Yankees

Video: MLB.com looks back on the 2015 Yankees, toward 2016

2015: 87-75, lost Wild Card Game

Key free agents: Chris Young, Stephen Drew

Why they could win: Luis Severino's emergence gives the Yankees a solid front end of the rotation, as he pairs with Masahiro Tanaka. And despite the offense's struggles down the stretch, Mark Teixeira is set to return, and the lineup remains a formidable one.

Offseason questions: What can the Yankees do to acquire a much-needed right-handed bat? (Moving outfielder Brett Gardner could be one option.) And are the Yankees ready to dole out a major contract to pursue a front-line starter like Price or Greinke?

Toronto Blue Jays

2015: 93-69, lost ALCS

Key free agents: David Price, Dioner Navarro, Marco Estrada, Mark Buehrle (retiring)

Why they could win: The Blue Jays boasted the best offensive attack in baseball in 2015, and their entire starting lineup will be back for '16. With Josh Donaldson, Jose Bautista, Edwin Encarnacion and Troy Tulowitzki, no team has a tougher heart of the order than Toronto. (Not to mention the Jays' stellar defense, too.)

Offseason questions: Marcus Stroman could very well become an ace, but the Blue Jays are set to lose three-fifths of their rotation -- including Price, whose arrival ignited their AL East title run. Plus, Bautista is 35, while Encarnacion and Russell Martin will each be 33 on Opening Day.

San Francisco Giants

2015: 84-78, missed playoffs

Key free agents: Tim Lincecum, Ryan Vogelsong, Mike Leake, Tim Hudson (retiring)

Why they could win: 2016 is an even year, so that should elevate the Giants right to the top of this list. But superstitions aside, the Giants may have the best battery in baseball when Madison Bumgarner is throwing to Buster Posey, and they have an extremely formidable lineup when healthy.

Offseason questions: Yes, Bumgarner can be other-worldly, but there's not a whole lot behind him in the rotation, unless Matt Cain can return to his old form. Expect the Giants to be one of free agency's most active teams on the starting pitching front.

Thinking outside the box ...

Few people foresaw success from the Mets, Cubs and Astros in 2015. Who might those surprise teams be in '16?

Minnesota Twins

2015: 83-79, missed playoffs

Key free agents: Mike Pelfrey

Why they could win: The Twins' youth movement began to bear its fruits in 2015, as Byron Buxton and Miguel Sano arrived and showcased their immense talent. If they perform as advertised and pitching prospect Jose Berrios does too, Minnesota could be the '16 version of the Astros.

Offseason questions: If Minnesota wants to remain competitive, it must add to its pitching staff -- both in the rotation and in the 'pen. Berrios' arrival could quell some concerns, but the Twins' rotation needs to get deeper and fast.

Cleveland Indians

2015: 81-80, missed playoffs

Key free agents: Mike Aviles

Why they could win: Francisco Lindor certainly seems like the real deal at shortstop, and his presence made the Indians' offense tick. Plus, Cleveland boasts a rotation that dominates opposing lineups, as no starting staff in baseball struck out more hitters.

Offseason questions: The Indians' lineup needs to get deeper behind Lindor, Michael Brantley and Jason Kipnis. With a realiable rotation staying in tact, the front office can focus on acquiring an impact bat or two in the offseason.