Talk about a seminal moment in American culture.

Some 103 million Americans shopped online over the Thanksgiving-Black Friday weekend, slightly more than the 102 million who went out to stores, according to the National Retail Federations’ Thanksgiving Weekend Survey conducted by Prosper Insights & Analytics.

While there is no comparable data from 2014 from this year’s survey, it is reasonable to believe that this marks the first time e-commerce shoppers outnumbered brick-and-mortar customers during the biggest shopping weekend of the year, given the soaring growth of online sales: Adobe earlier said on Sunday that e-commerce sales rose 19% between Thanksgiving and Saturday to hit $6.1 billion.

“It is clear that the age-old holiday tradition of heading out to stores with family and friends is now equally matched in the new tradition of looking online,” said NRF President and CEO Matthew Shay in a statement.

Many brick-and-mortar retailers have seen their e-commerce business boom. Kohl’s KSS Chief Executive Kevin Mansell told Fortune on Friday that the department store had its two biggest online sales days ever last week.

This year, stores have thrown their traditional Black Friday play books out the window, understanding once and for all that the consumers are going digital, and that AMZN isn’t bound by store hours like they are.

Best Buy BBY , Walmart WMT , and Target TGT were among the many retailers to trot out Black Friday deals early on Thursday morning, hours before shoppers could access the same discounts in stores. And on Sunday, many retailers, including Walmart and J.C. Penney JCP , were offering their Cyber Monday deals, effectively turning the event into Cyber Sunday.

“Everyone is doing their best to compete with Amazon, but Amazon is making it tough,” David Bassuk, managing director and co-head of the retail practice at AlixPartners, told Fortune. “The retailers need to have very powerful messages—we’re seeing more people glued to their laptops and mobile devices.”

The increased shopper count doesn’t mean that e-commerce is outpacing in-store sales. To this day, physical stores account for 90% of retail sales. But the trend is indicative of how much shopper habits have changed, and woe to any retailer that doesn’t keep up.

RetailNext estimated that in-store sales across the industry fell 1.5% on Thanksgiving and Black Friday. But retailers with strong e-commerce more than likely made up for that with online sales.

“It’s become a week-long event. Digital demand is way up, it’s been exceeding our plan and it has dramatically accelerated,” Kohl’s CEO Mansell said in an interview on Friday.

While we won’t know until the New Year how retailers fared, the NRF survey of 4,281 consumers found another bright spot: 151 million Americans went shopping in one form or another, well above the 136 million another Prosper had forecast two weeks ago.