No longer the domain of young, wealthy white men, the Internet has also attracted more minority shoppers, the study said.
"It shows how mainstream the Internet is becoming," said Lee Rainie, director of the Pew Internet and American Life Project, a nonprofit group that authored the study. "The online world now looks a lot like the off-line world."
Rainie said it was only a matter of time before women shoppers caught up with men, because women traditionally control the household's spending decisions.
Overall, 29 million American shoppers bought gifts online during the 2001 holiday season, spending an average of $392, up from $330 last year. A quarter of all U.S. Internet users did some of their buying online this year, versus a fifth of them last year. Of those, 58 percent were women.
The study also noted that a third of all online shoppers bought gifts from computers at work.
As the number of U.S. Internet users grows, so does the proportion of online shoppers, the study found.
Eleven million first-time shoppers spent money online this holiday season. Last year, 51 percent of American Internet users said they had purchased something online. This year, the number rose to 58 percent.
Measured by income, however, wealthy Americans are still the most likely to cyber-shop. Of households with incomes over $75,000, 39 percent bought something online, versus 15 percent of those earning less than $30,000.
The study cited cyber-shopping increases of 50 percent or more among blacks and Hispanics, alongside increases in overall Internet use, Rainie said.
But the largest proportion of Internet surfers - 43 percent of overall users - are window-shopping: looking for gifts and comparing prices online, then dashing off to the mall to make the deal.
"The Web site is becoming a promotion piece for the store," said Kurt Barnard, president of Barnard's Retail Trend Report, which covers consumer spending patterns. "They see the item on the screen and they compare it with others. But they want to go and see what it really looks like, maybe touch it."
Online merchants share some of the credit for the increase, said Dan Hess, vice president of comScore Networks, a research firm that tracks online buying behavior.
Hess said online stores designed Web sites to make shopping easier, while convincing customers of the security of their credit card numbers. Most were able to ensure that gifts arrived before Christmas.
"It's all about making the shopping experience more efficient, more reliable and more comfortable," Hess said.
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