Holiday shopping for many is no longer a sprint, but a marathon

(AP) -More than a dozen retailers from Wal-Mart to Target to Toys R Us opened on Thanksgiving Day and some stayed open overnight. Analysts say Thanksgiving shopping is becoming so popular that it's starting to take a bite out of Black Friday sales.

The Chicago research firm ShopperTrak says last year sales on turkey day were $810 million, an increase of 55 percent from the year before.

And on Black Friday last year, sales dropped 1.8 percent from the year before.