NEW YORK (AP) — The gravitational pull of Amazon Prime Day is so strong on shoppers it's benefiting other retailers as well, according to an early analysis from a key data group.

On Monday, the first day of its 48-hour sales event, large retailers, those that generated annual revenue of at least a billion dollars, enjoyed a 64% increase in online sales compared with an average Monday, according to Adobe Analytics, which measures 80 of the top 100 retailers on the web in the U.S. That compares to last year's 54%. In addition, niche retailers, those with annual revenue of less than $5 million, h...