NEW YORK (CNN/Money) - Online shopping showed a big holiday surge over Christmas week as shoppers flocked to the Internet for their last-minute gift buying, ringing up $950 million in total online sales, according to a market research firm's report.

ComScore Networks, an e-commerce market research firm based in Reston, Va., said Sunday that total sales for the week ended Dec. 26 rose 43 percent over the same period a year ago.

"With the exception of Christmas Day, when so many consumers turn their attention from gift shopping to gift giving, our data reported sales over $100 million dollars in each day of this latest week," Dan Hess, senior vice president of ComScore wrote in a report.

"This week's strength was driven by Christmas occurring one day later in the week than last year, plus continued robust sales across most major product categories," Hess said. "As expected, categories such as gift certificates and flowers were standouts, thanks to the ability to send such gifts purely online or with same-day delivery."

Through Friday, actual season-to-date sales are $11.7 billion, an increase of 29 percent versus year ago.

ComScore expects total online retail spending for the key holiday period of November and December to be up about 25 percent to 30 percent to between $12.1 billion and $12.6 billion. Holiday online sales in 2002 rose 19 percent to $9.7 billion