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With NFL teams kicking off training camp season, San Francisco 49ers quarterback Colin Kaepernick has jumped to the top of the list of best-selling player jerseys. Kaepernick's number 7 jersey was the top seller at NFLShop.com from April 1 through June 30, according to the league's Joanna Hunter. The 25-year old star is also No. 1 at Fanatics.com, said the online retailer's Meier Raivich.

After coming off the bench to lead the 49ers to Super Bowl XLVII, Kaepernick rose to number 4 in jersey sales last season, ahead of Tom Brady of the New England Patriots but behind Ray Lewis of the Baltimore Ravens. Electrifying rookie Robert Griffin III of the Washington Redskins led all jersey sales at the NFL's online store from April 1, 2012 through March 31, 2013.

The edgy, tattooed Kaepernick has "huge upside," said Brandon Steiner of Steiner Sports Marketing. "He's the kind of player people like." Seven of the Top 10 best sellers are QBs. Two linebackers make the list but they're both retiring: Lewis and Brian Urlacher of the Chicago Bears. There's one running back: Adrian Peterson of the Minnesota Vikings. Nike took over as the NFL's official outfitter last season. A youth Kaepernick jersey, for example, costs $69.95 at NFLShop.com, while men's and women's jerseys sell for $94.95 and $99.95, respectively. An autographed jersey will run you $559.95. No wonder sales of licensed merchandise based on sports leagues and events have become a billion dollar business. Retail sales rose to just over $13 billion in 2012, a 2.2 percent increase from $12.79 billion in 2011, according to The Licensing Letter. Apparel and accessories generated 46.6 percent. What about Tim Tebow? He's not in the Top 25 this summer as he tries to salvage his career with the Patriots. Joe Flacco of the Baltimore Ravens, the talented but dull QB who beat Kaepernick's 49ers 34-31 in New Orleans, ranks No. 25. Here are Top 10 best-selling players this summer, along with their position, jersey numbers and NFL experience.

—By Michael McCarthy, Special to CNBC.

Posted 19 July 2013 Michael McCarthy covers Sports Business for Advertising Age in New York. He's been a sportswriter for USA TODAY, Newsday, NFL and SportsBizUSA. Follow him on Twitter @MMcCarthyREV.

Colin Kaepernick, San Francisco 49ers

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Position: Quarterback Jersey Number: 7 Years: 3 The 6'4' Kaepernick seems to be everywhere, endorsing Jaguar's new F-Type roadster and posing nude in ESPN The Magazine's "Body Issue." But he ticked off some fans by tweeting a photo of himself wearing a Miami Dolphins lid. Forget "Tebowing." He inspired "Kaepernicking," where fans (including first lady Michelle Obama) kiss their flexed muscles the way he does after a touchdown. The former backup is one of the biggest steals in the NFL. He averages $1.3 million a year under his current deal, according to Spotrac.com, which tracks athlete salaries. That's $6.7 million less than the QB he supplanted, Alex Smith, who'll average $8 million annually with his new team, the Kansas City Chiefs. "He's a character with the tattoos and 'Kaepernicking,'" said Bob Dorfman of Pickett Advertising in San Francisco. "But can he prove he's not a fluke?"



Russell Wilson, Seattle Seahawks

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Position: Quarterback

Jersey Number: 3 Years: 2

Surprise. Wilson shot up to second place from No. 14 last season. Fans love an underdog. At only 5'11", Wilson is the shortest starting quarterback in the NFL. As a rookie, he beat out two higher-paid veterans, Matt Flynn and Tarvaris Jackson, for the starting job. Wilson is an even bigger bargain than NFC West rival Kaepernick: the third-round draft pick averages only $749,176 in annual salary, according to Spotrac. To put that in perspective, quarterbacks Joe Flacco of the Baltimore Ravens ($20.1 million) and Drew Brees of the New Orleans Saints ($20 million) will make nearly 27 times as much Wilson this season. Another boost: Swoosh gave the Seahawks uniform the coolest redesign of all 32 clubs last season. Wilson is part of the youth movement where stars 25 or younger boast three best-selling jerseys. Such as No. 3…

Robert Griffin III, Washington Redskins

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Position: Quarterback

Jersey Number: 10 Years: 2 Possibly fastest QB in history, the former Heisman Trophy winner from Baylor led all players with record jersey sales last season. The overall No. 2 pick in the 2012 NFL Draft was just as popular off the field, signing endorsement deals with Adidas, Subway, Gatorade, EA Sports and other sponsors. But RG3 is recovering from injury, and many fans may have bought his jersey already so his sales could suffer sophomore slump if he's not ready for the regular season.

Adrian Peterson, Minnesota Vikings

Adrian Peterson of the Minnesota Vikings Getty Images

Position: Running Back Jersey Number: 28 Years: 7 The highest-paid running back in the league ($13.7 million annually) earned every penny in 2012 by rushing for 2,097 yards (only 9 short of league record held by Eric Dickerson) and winning the NFL MVP award, a piece of hardware usually reserved for QBs. But what really captured the imagination of fans is the way Peterson did it all on a reconstructed knee. The player nicknamed "All Day" won "Comeback Player of the Year" award for his courageous return from injury in 2011. Ranked No. 23 in jersey sales last season.



Peyton Manning, Denver Broncos

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Position: Quarterback

Jersey Number: 18 Years: 16 Peyton's younger brother, Eli of the New York Giants, has two Super Bowl rings to his one. But Peyton is the more marketable Manning. He's the most successful NFL pitchman on Madison Avenue, earning $13 million annually in endorsements from sponsors such as Papa John's Pizza, Buick, Gatorade and DirecTV, according to Sports Illustrated's annual "Fortunate 50" survey. Those happiest about Manning's move to Denver Broncos after 14 years with Indianapolis Colts? Try retailers since his jersey ranked No. 2 behind Griffin last season.

But the 37-year old QB's arm looked tired. Will fans turn to younger stars?

Ryan Tannehill, Miami Dolphins

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Position: Quarterback

Jersey Number: 17 Years: 2 Who? Tannehill's solid 2012 season was overshadowed by the performance of other rookie QBs such Griffin, Wilson and Andrew Luck of the Indianapolis Colts, the No. 1 overall pick in the 2012 NFL Draft. But there's a lot of buzz this summer around Tannehill after the Dolphins added new offensive weapons such as free agent wide receiver Mike Wallace. But Tannehill "should enjoy it while it lasts" because he's a jersey bubble waiting to burst, Dorfman predicted. Not in Top 25 last season

Tom Brady, New England Patriots

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Position: Quarterback

Jersey Number: 12 Years: 14 No list is complete without three-time the Super Bowl champ and husband of Gisele Bündchen, the world's highest-paid supermodel. Brady's jersey sales are as consistent as his passing. He ranked No. 5 last season. But in the big money world of pro sports, you could argue Brady is underpaid. With $27 million in combined on and off the field earnings, he ranked 10th on Forbes' list of highest-paid NFL players in 2012. But as Tom Terrific nears end of his career, he's becoming more interested in endorsements. Brady has signed lucrative deals with Under Armour and UGG boots. He showed off his comedic timing in a "Funny or Die" video that went viral.



Ray Lewis, Baltimore Ravens

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Position: Retired Linebacker Jersey Number: 52 Years: 17 Lewis is heading to ESPN after winning his second Super Bowl ring. His overall No. 3 ranking in jersey sales last season was the highest for a defensive player since Pittsburgh Steelers safety Troy Polamalu led league during the 2010 season. He's made more money ($107 million) in career than any NFL linebacker except Brian Urlacher of the Chicago Bears, according to Spotrac. Lewis' No. 52 jersey will continue to sell in retirement. Many fans like to wear jerseys of their favorite all-time players, even if they haven't suited up for years. "Just look at all the Joe Montana jerseys at 49ers games," said Dorfman.

Aaron Rodgers, Green Bay Packers

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Position: Quarterback

Jersey Number: 12 Years: 9 After leading all players in jersey sales in 2011, and finishing second in 2010, Rodgers dropped to seventh last season. He's one of the Big 4 QB jersey sellers along with Brady and Peyton and Eli Manning, Steiner said. Like Brady, Rodgers is giving Peyton Manning a run for his money on Madison Avenue. He scored a hit ad campaign with his "Discount Double Check" commercials for State Farm Insurance. His "touchdown move" has spread into pop culture, always a sign that a campaign has struck a chord with consumers.

Brian Urlacher, Chicago Bears

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