By Ian Bush

PHILADELPHIA (CBS) – The calendar this year has retailers concerned: with Thanksgiving falling as late as it can, there are as few shopping days as possible between turkey day and Christmas.  And stores are responding with big sales a lot earlier than we’re used to.

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“Walmart, Best Buy, Newegg, and Amazon — the four big ones when it comes to online and when we think of Black Friday deals — they all hit the ground running on November 1,” says Brent Shelton, spokesman for the deals portal  “They’re offering some kind of sale almost every day on particular items. They’re being very aggressive with toys and electronics.”

With Thanksgiving on November 28th, the run-up to Christmas features fewer shopping days — just 26, as compared to 32 last year.

But Eric Karson, associate professor of marketing at the Villanova School of Business, says his research shows there’s little reason for retailer worry.

“There is absolutely no correlation statistically between the number of shopping days and holiday spending,” Karson explains.

He’s run the numbers from the past dozen years of shopping days vs. sales figures and says they match up with the anecdotal evidence.

“Do you know anyone who’s saying, ‘hey, there’s fewer shopping days this holiday season, so I’m going to buy my friends and family fewer presents?'”

Reporter: “No, I haven’t heard that at all.”

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Karson: “No, I haven’t heard that either — nor, frankly, could I imagine it.”

He sees online sales ticking up double-digits over the holiday season. Not so much for brick-and-mortar retailers — though Karson believes some will benefit from price matching and from shoppers’ desire for instant gratification.

Shelton says FatWallet, which posts Black Friday sales ads, has seen earlier-than-ever “leaks” of those circulars.

“Best Buy, even, has already come out with a teaser ad — it was only six items, but it’s given us an idea of how they’re going to lower prices for Black Friday,” he says. “Lowes has done the same thing. It’s possible that the aggressiveness with the early sales is working so they can hold on to their actual ads a little longer.”

Shelton says retailers and shoppers alike are boosted by the meteoric rise in mobile shopping — via smartphone and tablet — and stores are pushing consumers to open their inboxes.

“They want you in their email channel so they can basically advertise to you on a daily basis,” he explains. “They’ve been very aggressive with that this year — and to reward you, they offer these attractive deals that keep your attention through the process until we get to the bigger shopping days: Thanksgiving, Black Friday, and Cyber Monday.”

The country’s economic picture is far from rosy, with growth tempered by lingering signs of weakness.  But Karson says people — to the extent they’re financially able — still make the effort to put gifts under the tree.

“A Deloitte study finds people making over $100,000 would spend about $780 on holiday shopping this year,” he says. “People with lower incomes spend about $320 for gifts. But the government seems to be functioning again, and the stock market is going up.  So people are looking for a reason to exhale and have a little fun, and spend money on people they care about.”

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