U.S. online holiday sales up, hit $24.6 billion

NEW YORK -- U.S. online sales in the holiday season to date are up 15 percent to $24.6 billion, according to comScore.

The Reston, Va., research firm says sales on six individual days during the first 39 days of the November-to-December shopping season have exceeded $1 billion, led by Cyber Monday, the Monday after Thanksgiving.

"As we enter what will be the heaviest week of the season for online retailers -- beginning with 'Green Monday' on Dec. 12 -- all signs are now pointing to a strong finish to the season," comScore Chairman Gian Fulgoni said.

Over the past six years, "Green Monday" -- traditionally the second Monday of December -- has consistently ranked among the top spending days of the season.