Forrester Research analyst says Americans will spend $89B online on holiday shopping this year

This year more Americans than ever are expected to make their lists, check them twice, and then click the "add to cart" button.

Forrester Research says it expects U.S. consumers to spend $89 billion by Christmas. That's up 13 percent, or about $10 billion, from a year ago.

Analyst Sucharita Mulpuru says she thinks online shopping will comprise 14 percent of total retail spending over that period. She estimates that 3.4 million Americans will try holiday shopping online for the first time this year.

Mulpuru said her estimate would be higher if Thanksgiving were occurring earlier. The holiday always falls between Nov. 22 and 28, and it will be on Nov. 27 this year.