Mary Bullard has a sort of love-hate relationship with Ross Dress for Less.

She doesn't like the stores because they have narrow aisles, long lines and "way too much stuff."

But all that isn't enough to keep her away: The Corona, Calif., resident spent a recent lunch hour at a Ross in Santa Ana enthusiastically making her way along a rack of women's pants.

Latching onto a pair of Levi Strauss hip-hugging, boot-cut jeans, she was delighted to see they were marked down to $10.99 from $48. "How could that be? They look fantastic."

They didn't fit. No problem. "You've just got to keep digging," said Bullard, a 45-year-old shipping department worker. "And it's fun."

Behold the treasure hunt syndrome, as analysts call it, a willingness to swap the niceties of department stores for the thrill of finding a bargain. It is boosting the fortunes of so-called off-price retailers, such as Newark, Calif.-based Ross Stores Inc. and its chief competitor, TJX Cos., parent of the T.J. Maxx and Marshalls clothing chains.

TJX, based in Framingham, Mass., recently posted a 29 percent jump in quarterly profit. A consensus of analysts surveyed by Thomson First Call Inc. expects the retailer to post third-quarter earnings per share of 65 cents, up 14 percent from the year before.

The company has racked up nine years of sales and earnings growth and has set its sights on a nationwide expansion that ultimately could triple its stable of 573 Ross stores. The company's Baltimore-area outlets are in Catonsville, Columbia, Owings Mills, Parkville and Towson.

'Practically free'

The hook for consumers: high-profile brands -- from Quiksilver and Tommy Hilfiger to Liz Claiborne and Perry Ellis -- at low-ball prices.

"They've got things that are practically free," said Anne Hinkey, a 59-year-old real estate broker from Huntington Beach, Calif., shopping in the Santa Ana store. "Any time I'm by a Ross Dress for Less, I just cruise through and see what I find."

Keeping in mind shoppers' seemingly insatiable demand for discounts, Ross next year will launch an even-lower-priced chain, dubbed dd's discounts, to target lower-income families in urban and suburban neighborhoods.

"We think this is an underserved market," Ross Chief Financial Officer John Call said, projecting that the initial launch of 10 stores in the West — most of them in California — eventually could expand to at least 500 nationwide. "From an apparel standpoint, we don't see anyone doing it well, particularly on the West Coast."

The average price of an item purchased at Ross is $10. At the new dd's discounts stores, the average price will be lower still, Call said. The new chain will have a similar mix of products as those offered in Ross stores, which include accessories and housewares. But instead of merchandise that might be found at Macy's or Robinsons-May, dd's discounts will carry brands more like those sold at Sears or JCPenney stores.

TJX launched a similar chain store four years ago and now has nearly 100 A.J. Wright stores, mostly on the East Coast -- including in the Westside Shopping Center in Baltimore, as well as in Dundalk, Glen Burnie and Woodlawn.

That division posted a 56 percent sales increase for the quarter ended Oct. 25. Sales at A.J. Wright stores open at least a year, a key industry indicator, rose a hearty 14 percent.

Winning formula

Although department stores have been struggling for years, and some specialty-store companies, such as San Francisco-based Gap Inc., are trimming square footage, Ross and TJX continue expanding at a combined rate of 10 percent to 12 percent, according to a report released this month by Brian Tunick, an analyst with J.P. Morgan.

In addition, both Ross and TJX are spending $200 million to $250 million a year to buy back stock and both are paying dividends to shareholders, the report said.