The American Atheists organization, which posted the billboard reading, "You know it's a myth. This season, celebrate reason," in late November, said its ad was removed when its lease on the billboard ran out after a month, CNN reported Friday.
The "God is" billboard that replaced the atheist message was paid for by the Times Square Church of New York and the organization's Web site said it was a direct response to "atheist billboards near the Lincoln Tunnel declaring Christmas a myth."
An American Atheists spokesman said the group spent $20,000 renting the billboard space and has since received $65,000 in donations.
"We received e-mails from hundreds of agnostics and atheists who heard about the billboard and had never heard about us who thanked us for being there and letting them know they're not alone, and that was our target audience from the get-go," spokesman Blair Scott said.