STORES AND websites fight for shoppers.

More and more shoppers will buy their Christmas presents from home this year with a click of a computer mouse or a tap on a mobile-device screen.

A battle is raging between big brick-and-mortar stores and their online counterparts this season, pitting the likes of Wal-Mart Stores Inc. against Amazon.com Inc. as they offer cyber deals earlier and for longer to attract cautious consumers.

“We see store-based retailers enhancing their online presence,” said Steven Barr, U.S. retail and consumer leader for audit firm PricewaterhouseCoopers. “It is a really challenging time to be a retailer. The retailers have gone heavily promotional for the holidays.”

The National Retail Federation expects online sales to grow between 6 percent and 8 percent this year to as much as $105 billion, outpacing big-box retail shopping.

With such online growth expected, even Black Friday — the in-store shopping phenomenon that traditionally kicks off the Christmas shopping season — has relinquished sales typically reserved for the day after Thanksgiving to online promotions.

Analysts say the move to more online sales signals a shift in demographics and highlights the fact that many consumers plan to spend less money this year, forcing retailers to offer bigger deals to draw shoppers to their websites and stores.

The rise of the millennial generation — those between

ages 18 and 34 — is what is pushing consumer spending to online.

“We’re really starting to see the influence of the millennial shopper in a way we haven’t before,” said Stacy Kemp, a principal with accounting firm Deloitte. “Consumers are seeing the shopping season as a zone. And the specific days as Black Friday or Cyber Monday are not as important as they used to be.”

And it’s not just the venue consumers are using to shop that is changing. There is a shift in what people are buying.

Instead of purchasing sweaters and video games, millennial consumers are spending more on trips to the spa, to the theater or even to Europe. And because of this dynamic, entertainment and travel websites are starting to offer discounts this season, analysts said.

“There’s a generation that cares more about experiences than they do things,” Barr said. “Millennials really are transforming that overall shopping experience.”

And, he said, “This generation, the millennials, are influencing shopping behaviors of higher generations more so than any generation I can recall.”

Also forcing stores to offer more sales throughout

the Christmas season is hesitancy by consumers, who are concerned about the economy and flat wages, to spend money.

Price will be the major influence on purchases this year, as shoppers look to get more for their money, analysts said.

“Online percent of sales continue to grow. Traditional retailers … are trying to get their fair share of that against the Amazons of the world,” said Neil Stern, senior partner at McMillan Doolittle, a retail consulting company.

“They’re trying to both protect their stores — the traffic going to their physical store — but also recognizing they have to compete with online stores,” he said.

Many box stores, including Macy’s, Wal-Mart and Target, are focusing on growing their online business this season.

For example, Wal-Mart, instead of waiting for Monday to offer big online deals, is starting its Cyber Monday deals on Sunday.

The company, which opened its doors to shoppers at 6 p.m. on Thursday, also started its Black Friday deals online at 2 a.m. on Thanksgiving.

“The 2015 holiday season started as soon as people turned their porch light out for Halloween,” Barr said. “Black Friday is still a very important event on the retail calender but I think it’s moved from being the event to an event.”