CHICAGO (Reuters) - Forget the turkey and the football — if it's Thanksgiving Day, why weren't you shopping?

US retailers, trying to squeeze every extra cent possible out of shoppers, were open yesterday for Thanksgiving, trying to get a jump on the holiday shopping season.

Among the retailers that opened yesterday were Wal-Mart Stores Inc's US discount stores, 850 of Gap Inc's Old Navy stores as well as some of its Gap and Banana Republic stores; and Sears Holdings Corp's namesake department stores and Kmart discount stores.

For shoppers, it was a chance to find some early deals on electronics and clothes to fill the lull before the holiday meal or to avoid the throngs that will shop on "Black Friday" — the traditional start of the holiday shopping season.

"I'm actually kind of bored so I'm killing time, trying to catch some bargains," said Vonney Brown, 40, of Bayonne, New Jersey, said at a Sears in the Newport Centre Mall in Jersey City, where there appeared to be as many employees as customers at midday yesterday.

"I'm not coming out on Black Friday," said Brown, who was joined by his wife and two children. "You got to be out of your mind."

For retailers, opening the stores amounts to extra sales at the start of what is expected to be the best holiday shopping season since 2007 — before falling home prices, tight credit and soaring unemployment forced consumers to cut spending.

The holiday season is essential for many retailers, who depend on it for a big part of their profits for the year.

But people shopping on Thursday will still only be a fraction of the 138 million the National Retail Federation hopes to see on Black Friday, the following day.

"It's an add-on," Brian Sozzi, an analyst at Wall Street Strategies, said of stores opening on Thanksgiving.

"If one of the retailers that is open on Thanksgiving has a bad day, I don't think it is going to make or break the season," he added.

More than 18 million adults went shopping on Thanksgiving Day in 2009, according to a survey from the National Retail Federation.

"Our decision to stay open on Thanksgiving Day was based on our customers' response and desire to have an extra day to shop," David Friedman, president of marketing at Sears Holdings, said in a statement earlier this month.

Sears, which saw sales at its namesake department stores plunge in the latest quarter, has opened stores on Thanksgiving for the first time in a bid to halt that slide.

Moody's Investors Service senior analyst Charlie O'Shea said a Sears store he visited in Watchung, New Jersey, about 25 miles west of Manhattan, was offering steep discounts, particularly on apparel, yesterday.

"This is the most aggressive I've seen them be," he told Reuters as he toured strip malls and shopping centres in New Jersey to gauge shopper traffic.

For example, he said, a $25 thermal shirt for men was going for $10. And Sears was offering an extra 5 percent off on purchases made on a credit card.

But yesterday was also a day for online shopping and many retailers were featuring specials on their websites.

WalMart.com planned almost 150 online specials yesterday, triple the number of those it offered last year, a spokesman said earlier this month.

Those included Nintendo DSi gaming value bundle for $169, down from $199. The world's largest retailer also is offering free shipping on electronics as it tries to compete with the likes of online giant Amazon.com.

Amazon is continually refreshing its online deals and includes a countdown clock that shows how long each item is left on sale. Items on Thursday included a silver diamond snowflake pendant at $42.99, a 52 percent discount. Items at Target.com included a Magnavox 46-inch HDTV for $779, or $100 off the previous price.

Consumers, who account for about 70 percent of the US economy, appear to be in the mood to shop. On Wednesday, the government reported personal spending rose 0.3 percent in October compared with the previous month.

Other signs the economy might be gaining steam include a two year-low in a closely-watched measure of jobless benefits.