Well what do we have here…

A new campaign is asking men to take a new look at the “Under” in “Under Armour.”

Under Armour, the maker of sports apparel aimed at athletes and the athletic, is expanding its presence in the underwear category by broadening its collection of boxer briefs. The campaign promotes the new offerings in the Boxerjock line with the theme “You’ll never wear regular underwear again.”

The campaign features Cam Newton, who signed an endorsement deal with Under Armour in February 2011 that was called the largest ever given an incoming National Football League rookie. Mr. Newton, the quarterback for the Carolina Panthers, also appears in ads for Under Armour football gear like the new Highlight cleat.

The new Boxerjock products are being sold by two department store chains, Macy’s and Nordstrom, in addition to the usual places Under Armour has sold underwear: sporting goods stores and online at underarmour.com. Under Armour products have been in Nordstrom before, but this is the first time the brand will have a presence in Macy’s (and on macys.com).

The campaign, created internally at Under Armour, includes print and online ads, social media, ads in stores, direct mail and events. Optimum Sports, part of the Omnicom Media Group division of the Omnicom Group, is handling the media planning and buying.

The budget for the Boxerjock campaign is estimated at $1 million. That is a sizable amount for a company that spent nothing to advertise its underwear lines last year, according to the Kantar Media unit of WPP, and only $91,000 in 2010. The total Under Armour ad spend was $10.5 million in 2010, Kantar Media reported, and $12.1 million in 2011.

The Boxerjock campaign underlines the ferment in the men’s underwear market, once a sleepy corner of the clothing industry dominated by heritage brands like BVD, Fruit of the Loom and Hanes. The changes that began with labels like Calvin Klein are accelerating as marketers respond to what Women’s Wear Daily this month described as “surging demand for fashion, color and performance” products among shoppers.

Just how competitive and crowded the underwear category is getting was demonstrated in February, on the biggest day of the year for advertising: Super Bowl Sunday. The H&M retail chain ran a Super Bowl spot for the first time, to promote David Beckham Bodywear, a new line of underwear endorsed by the soccer star.

Under Armour has long played up the performance aspects of its products, defining its mission as “Make all athletes better.” The new boxer briefs are meant to add a fashion component to the brand’s undergear.

“The new collection gets to the design elements without sacrificing the performance,” says Stuart Redsun, senior vice president for global brand marketing at Under Armour in Baltimore. He joined Under Armour last October after serving as senior vice president for marketing at the Sony Corporation of America.

Underwear represents “the first layer of gear people put on every day,” Mr. Redsun says. “We’re expanding the Boxerjock collection to go from sports-specific to a broader use.” The “sports-specific” reference is to products meant to be worn while playing, say, baseball or football.

The new boxer briefs are also being aimed at “a broader range of consumers,” Mr. Redsun says, by offering “high comfort” along with “high performance.”

“It’s really the next generation” of underwear, he adds.

The Boxerjock campaign is meant to fit in with the ads for other Under Armour merchandise, Mr. Redsun says, and reflect “the Under Armour attitude and tonality” as embodied by themes like “Protect this house. I will.”

“We bring the Under Armour brand slant to any category we go into,” he adds.

For instance, the ads “showcase the product in ways that are heroic,” Mr. Redsun says. “You won’t find the runway models.”

Indeed, the thighs of some of the models wearing the Boxerjock products on underarmour.comare about as wide as the bodies of the models found in ads for fashion underwear brands.

And some ads carry headlines intended to draw double takes like “Cam Newton doesn’t wear underwear …” (Those ads are part a series, which continues, “He wears the Under Armour Boxerjock.”)

The new Boxerjocks come in four varieties, named U.A. Original, U.A. Mesh, U.A. Elite and U.A. Touch. Each proclaims on packaging that it offers attributes that include “four-way stretch comfort,” “maximum ventilation and breathability,” “streamlined performance fit” and “squeeze-free snug fit.”

The prices for the new boxer briefs range from $20 to $30 apiece.