NEW YORK (CNN/Money) - Executives at Sports Illustrated see something even more beautiful than scantily clad supermodels when its annual swimsuit issue rolls off the presses -- they see a significant portion of their profits for the year.

The issue is probably the most profitable single issue of any magazine, according to Abe Peck, chairman of the magazine program at Medill School of Journalism.

Click here to see the swimsuit feature at SI.com.

The magazine says the issue, which came out this week, is expected to sell an extra 1.4 million copies over its normal weekly circulation of 3.15 million. At $5.99 a copy, those extra newsstand sales alone add about $8 million in revenue.

Add to that an estimated $34 million in advertising revenue for 115 pages of ads in this year's special issue, sold at an 18 percent premium over normal ad rates, and the issue has become an important profit center for the publisher, even one as large as Sports Illustrated's owner AOL Time Warner Inc. (AOL: Research, Estimates). And those numbers, which are expected to lead to record revenue this year, probably only scratch the surface of the revenue impact of the issue for the company.

"I'm sure at a company like Time Inc., especially in light of AOL's problems, when this issue hits the collection plate, people give it an 'Amen,'" Peck said.

The issue is timed to come out at a lull in the sports schedule, when football is over, baseball has yet to begin, and basketball and hockey are not yet nearing the playoffs. So the timing helps lift sales and revenue when the magazine needs it the most.

Sports Illustrated's swimsuit franchise extends to calendars and videos.

"The momentum it gives us in the beginning of the year to carry through and meet our numbers is very important to us," said Sports Illustrated Associate Publisher John Rodenburg. "Having a record year this year really helps us on way to make our numbers for the quarter and the year."

Sandy Padwe, a professor of journalism at Columbia University and a former senior editor at Sports Illustrated, said that he was told 10 years ago that it was a $50 million property in its own right, and he's sure that revenue has only increased in the intervening years.

"Some of us were making an argument to get rid of the swimsuit issue because we found it had inherent problems with being offensive to some readers," he said. "We were laughed at and told, 'Do you think Time Inc. is going to give up a property like that?'"

The issue has spawn a slew of imitations, including a National Geographic swimsuit issue and a swimsuit issue last year for Sports Illustrated Women, the former sister publication which used male athletes as models. That issue wasn't enough to save that publication, which halted publication in December.

Sports Illustrated uses swimsuit videos and DVD's to try to attract new subscribers.

The SI swimsuit issue still spawns some protests that it is offensive to women, but the magazine says that the issue has about 30 percent women readership, which it said is up from 23 percent for a typical weekly issue.

Peck said that despite some limited protests the issue generates among feminists and some journalists, the magazine has an easier time with both newsstand sales and ad sales than more explicit publications such as Playboy, or even Maxim, the latter of which, like Sports Illustrated, does not publish photos of totally nude models.

"It's easier for a media buyer to go to a client and schedule an ad in this issue, a magazine their boss probably reads, than it is to do some of the others," Peck said. "It's polite skin in a reputable magazine."

Padwe said the limited nature of the publication -- only once a year -- also helps build both the publicity and thus the sales associated with the issue.

"They've done a great job promoting it and making people anticipate it each year," he said. "If it was out every week, it'd ruin it."

The company also has found new ways to leverage the marketing potential of the issue.

The magazine has a swimsuit video and DVD offer for new subscribers. It also offered a preview of the issue to America Online subscribers early Tuesday, part of the company's new strategy to provide exclusive content from its Time Inc. unit to customers of its embattled Internet service provider, which last quarter showed its first decline in membership.

SI.com, which like CNN/Money is a unit of AOL Time Warner, had about 900,000 visitors check out its swimsuit feature Tuesday, including a live Webcast of the exclusive launch party which drew about 200,000 visitors Tuesday evening.

The swimsuit feature generated about 15 million page views on SI.com, nearly three times the daily average year-to-date leading up to Tuesday's launch.