By Ian Sherr

CHICAGO (Reuters) - With only 160 shopping days left, it's beginning to look a lot like Christmas in some stores.

After U.S. retailers posted 10 straight months of sales declines, some chains are trying to bring holiday spirit -- and revenue -- to the summer with "Christmas in July" promotions.

Both Sears Holdings Corp (SHLD.O) and privately held Toys R Us TOY.UL are holding wintry holiday-themed events this summer ahead of their back-to-school promotions, which usually start around the end of July.

Sears began its sale last week. The company decked the halls of about one-third of its 930 namesake stores, as well as its Sears and Kmart websites, by touting cold-weather gear and snow-topped porcelain collectibles at the same time as it sells inflatable swimming pools, sundresses and sandals.

Toys R Us is planning a similar event, but with more emphasis on holiday-themed pricing of roughly 50 percent off bicycles, video games, doll houses and portable DVD players.

While the chain won't be selling holiday merchandise, it will be bringing unseasonal cheer, complete with Christmas cards and candy canes, to its stores on July 25.

"Everyone needs a little Christmas, right this very minute," the company said in a release last week.

Even the MoMa Design stores, which are part of New York's Museum of Modern Art, are getting in on the action, selling holiday-themed greeting cards, a fold-up gingerbread house and polar bear Christmas tree ornaments as part of a "Last Chance Summer Sale."

The year-end holiday season is the most important for U.S. retailers, which can sometimes ring up as much as 40 percent of their annual revenue in the weeks between the U.S. Thanksgiving holiday in late November and Christmas on December 25.

SANTA HATS IN SUMMER

Sears and Toys R Us have not disclosed expectations for their promotions. But they may be hoping for success similar to that of high-end department store operator Nordstrom Inc (JWN.N), whose annual anniversary sale in late July features discounts on cold-weather jackets, boots and coats.

The event has become so popular, Nordstrom said, that its second quarter, which this year began on May 3, is now as important as its fourth. And the first day of the sale has become the company's biggest day of the year.

It is not unusual for retailers to stock up on fall sweaters and other items in July, but products like scarves and down jackets do not usually arrive until later in the year.

While the Nordstrom promotion includes cold-weather clothing, spokeswoman Brooke White said there would be no mention of reindeer or Santa Claus.

"Our customers really love the fact that we do not celebrate the holidays until the day after Thanksgiving," she said, "and we have no plans to change that."

But Toys R Us and Sears will embrace those yuletide images.

In fact, the Salvation Army, whose bell-ringing workers are known to flank store entrances in Santa hats during the holiday season to collect money for the nation's poor, will be at these chains and other locations this month.

"It's something we've gotten behind, and the community has embraced," said Stephen Warren of a Salvation Army branch in New Hampshire about its July donation drive. "People are not only in need during Christmas."

NAUGHTY OR NICE?

Ken Perkins, president of research firm Retail Metrics, questions whether this season-switching will gain traction with U.S. consumers who have been dogged with falling home values, rising unemployment and other financial worries.

"Consumers have way too much on their minds to be worried or even thinking about five or six months from now," he said.

At a Sears store in downtown Chicago, the reviews were mixed.

Beverly Lewis, a librarian from South Dakota, said she had no problem buying winter items in July if the price was right.

"A sale is a sale," she said.

But 35-year-old Todd Smith of Chicago took a different view.

"It's very odd," he said. "It makes me think they're desperate."

(Reporting by Ian Sherr; Editing by Lisa Von Ahn)