It begins tomorrow.

Wal-Mart will deck out its stores in red and green Friday night and early Saturday, immediately after the leftover Halloween candy goes on sale, for what it and other retailers consider the start of the holiday shopping season.

Gone are the days when decorations, merchandise and promotions would gradually appear during the first few weeks of November, said Brian Yarbrough, a retail analyst with Edward Jones.

“Now it seems like it goes straight from Halloween to Christmas,” he said. “Every year, it gets earlier and earlier.”

Earlier deals are a way to drive consumers to malls and stores, which continue to adjust to pressure from online sellers.

This holiday shopping season will once again be a fierce battle for shoppers’ dollars. Most forecasts are calling for a 2 to 4 percent bump in sales.

“I would expect it to be at least as competitive as last year,” Steve Bratspies, Wal-Mart’s executive vice president for general merchandise, told reporters in a conference call Thursday. “It rarely goes backward.”

Wal-Mart on Saturday will start promoting 20,000 price rollbacks on a broader assortment of items than last year, including popular holiday gifts such as an Xbox One and a Samsung 46-inch HDTV. On Monday, it will hold a 24-hour online sale that Bratspies said will have deals similar to those offered on Black Friday and Cyber Monday.

The nation’s largest retailer has also expanded the number of products available for sale on its website to 7 million, about 1 million more than last year.

Wal-Mart, though, will not match Target’s holiday promotion of free shipping on any size order. Instead, Wal-Mart executives noted that it will offer free shipping on a curated list of 100 holiday gift items starting Saturday and noted that a majority of its items are available for free shipping, but they require a minimum $50 purchase.

Target, which raised the bar by offering free shipping on all online orders last week through the holidays, is offering 50 percent off a different toy everyday from Sunday to Dec. 24 through its mobile coupon app Cartwheel.

Amazon.com will also start rolling out its holiday deals on Saturday. The online retailer says it will have 15,000 lightning deals, which last for a short time, throughout the season and two “Deals of the Day” every day through Dec. 22.

Office Depot and OfficeMax are launching holiday deals on Sunday with early Black Friday and “Every Monday is Cyber Monday” deals throughout the season.

Egged on by retailers, consumers for a decade have steadily shifted their holiday shopping into November from December, said Bill Martin, the founder of ShopperTrak, a market research firm in Chicago.

With so many promotions earlier in the season, the importance of Black Friday and Cyber Monday for consumers is waning, said James Russo, senior vice president of global consumer insights for Nielsen, another research firm.

“It’s diminishing because the definition of Black Friday is changing,” he said. “They are opening on Thursday or announcing promotions earlier. So that extends the holiday season.”

Macy’s has already announced that it will open at 6 p.m. on Thanksgiving night, two hours earlier than last year. On Thursday, Kohl’s announced that it would also open at that time on the holiday.

During their conference call, Wal-Mart executives would not talk about their Black Friday plans. And while they noted the retailer is considering matching online prices of competitors such as Amazon during the holidays, they said they have not made any final decisions. Target and Best Buy already match prices of Amazon and other major online retailers.