The holiday shopping season kicked off on Thursday even before the turkey was carved, as retailers, worried that gift buying may slow this year, posted special deals on their Web sites on Thanksgiving day.

Numerous retailers, including Wal-Mart Stores Inc, Best Buy Co Inc and Circuit City Stores Inc, are offering special deals online.

Wal-Mart on Thursday was advertising on its Web site a Magnavox 47-inch flat-screen television for $1,298, while Circuit City offered a Sony Blu-ray disc player for $399.99.

Black Friday, as U.S. retailers call the day after Thanksgiving, starts the ultra-competitive holiday shopping season. Retailers traditionally open their doors in the early morning hours and offer special, limited-time discounts.

This year, retailers have rolled out holiday deals and promotions earlier than ever, using Web sites more extensively to advertise special discounts.

The scramble in cyberspace for consumers comes as retailers worry U.S. shoppers may reduce spending in the face of higher food and fuel costs, the slowing housing market and the credit market crunch.

Walmart.com CEO Raul Vazquez said traffic to the retailer's Web site has been rising headed into the Thanksgiving holiday shopping weekend.

We would expect to get around 10 million visitors to its site on Thanksgiving, he said. That would be a big jump from typical traffic of 2 million daily visits during other times of the year.

Some retailers allowed shoppers to sign up on their Web sites to receive cellular phone text messages alerting them when new sales and discounts are posted.

The Web sites of most major retailers appeared to be functioning well, with no slowdowns.

JCPenney is even offering customers wake up calls to get them to stores in time for the 4 a.m. doorbuster sales.

Some malls are opening as early as midnight on Thanksgiving night, holding special Midnight Madness shopping events.

(Reporting by Euan Rocha and Nicole Maestri; Editing by David Gregorio)

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