Holiday sales are hopping online, several new studies indicate.

E-commerce sales hit $2 billion last week, the largest weekly amount ever recorded, ComScore Networks reported on Tuesday. Meanwhile, Monday was the biggest online sales day of the year, with sales reaching $367.05 million, according to While ComScore's numbers include sales of travel, BizRate's do not.

"E-commerce is doing great," said Helen Malani, a spokeswoman for Los Angeles-based BizRate.

Even so, it's unclear whether online sales will meet analysts' expectations. ComScore, for instance, projected that nontravel, nonauction sales in the fourth quarter would grow 27% over the same period last year to $13.8 billion. Thus far, such sales to date have grown about 24% to $9.3 billion.

The shortfall is nothing to worry about, said Dan Hess, vice president of ComScore. "The early weeks of the quarter showed growth rates that were not consistently as strong. Now that the season's in full swing, we're going to see that gap closing fast," Hess said.

Meanwhile, BizRate projects that e-commerce sales are already in line with its projections. The research firm had forecast that excluding travel, auctions and event tickets, online sales in the fourth quarter would grow 35% over last year to $16.8 billion. For the period of Nov. 1 to Dec. 9, sales have totaled $8.4 billion, up 43% from the same period last year.

The bright outlook for e-commerce comes against a cloudy time for traditional retailers. Bricks-and-mortar retailers reported mixed November sales results last week, with companies such as the


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posting significant improvements, while others such as


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posting disappointing or decreasing sales at comparable stores.

E-commerce's success may be coming, at least in part, at the expense of traditional retailers, the new studies indicate. A survey of online shoppers by the National Retail Federation's indicates that 35% of them plan to spend more money online this holiday season compared with last year, while 26% expect to spend less. In contrast, only 15% planned to spend more at traditional stores, while 46% expected to spend less.

Likewise, a survey of online users by Nielsen/NetRatings indicates that they are devoting a larger percentage of their holiday shopping budget to online spending. Last year, for instance, Internet users planned to spend more than 79% of their budget in stores, compared with about 6% in catalogs and 15% online. This year, they expect to spend about 77% in stores, compared with about 6% in catalogs and nearly 17% online.

That may seem small, but it's a significant shift, said Patrick Thomas, a senior analyst with Nielsen/NetRatings. "Retail dollars are being spent online because of the satisfaction and convenience," Thomas said.

Driving online sales this year has been a flurry of free-shipping offers from the likes of

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and sellers on


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, e-commerce analysts say. On Monday alone, 32% of online purchases were influenced by free shipping offers, said BizRate's Malani.

"Certainly, we're seeing that free shipping without a doubt is the major driving force," said Hess.

While free shipping has been driving sales, some have questioned whether e-tailers offering such deals will be able to do so profitably. Amazon, for instance, lost $10 million on shipping charges last quarter and some Amazon analysts have argued that the company has set too low a threshold for free shipping. The company currently offers to ship for free most orders totaling more than $25.

The big beneficiaries of the boom in online shopping appear to be the entrenched players, companies such as Amazon and eBay. According to the eSpending report, put together by Nielsen/NetRatings, Harris Interactive and Goldman Sachs, Amazon accounted for more than 35% and eBay nearly 11% of online sales of books, CDs, videos and DVDs in November. The companies also combined to account for nearly a third of all online consumer electronics sales last month.

eBay and Amazon "are definitely benefiting" from the growth in online sales, Thomas said. "They have huge bases of customers and they maintain these people year-round."

Some of the categories that have shown marked improvement this holiday season online compared with last year include toys, home and garden products, sport and fitness products, jewelry and watches, each of which has seen sales growth of more than 60%, according to ComScore Networks. Meanwhile, computer hardware sales jumped 51% last week to $326 million.

"After a few months of relative softness, computer hardware has shown good growth," Hess said.