Amazon's lift was largely the result of Prime Now, which offers one- and two-hour delivery in dozens of markets. The service is available for two dozen categories, including household items and electronics.
Known for its tight delivery windows, Amazon has demonstrated to Prime members that it can get them last-minute orders on time. In a news release last month, the company said that Dec. 23 was the biggest day ever for Prime Now, and that members ordered three times more items through the service compared with last year.
"2017 is clearly becoming the year [once again] that Amazon's competitors have no choice but to think differently in order to counter Amazon's dominance in the e-commerce channel," Ken Cassar, principal analyst at Slice, told CNBC in an email.
He added that Wal-Mart's more than $3 billion investment in Jet.com "will soon be seen as a bargain."
Also in December, Amazon said it had recruited more shoppers to its subscription Prime program than during any other holiday season, helping it reach a sales record. It shipped more than 1 billion items worldwide with Prime and Fulfillment by Amazon.
Part of that lift may be the result of a more aggressive marketing campaign. An analysis released by MediaRadar last month found that Amazon dramatically increased its spending on TV and digital ads this season.
Adobe Digital Insights on Wednesday said online sales increased 11 percent this holiday season, to $91.7 billion. That was in line with its initial forecast. Adobe's data measures 80 percent of all online transactions from the top 100 U.S. retailers.