An NBC Sports executive says advertising sales for the 2014 Winter Olympic Games in Sochi, Russia, are going "exceptionally well," with the company projecting $800 million in revenue.

The first phase of the Olympics ad sales - to companies that will spend at least $10 million to $15 million during the Games - was completed several months ahead of schedule, executive vice president Seth Winter said this week.

The first phase will account for about 75 percent of the more than $800 million expected total advertising take for the Sochi Olympics. The remaining ad sales will be "scattered" and for lesser amounts closer to the start of the Olympics in February, he said.

Comcast Corp. owns NBC Sports through NBCUniversal. In 2011 it acquired the TV rights to the Olympics through 2020 for $4.4 billion.

NBC projects about $50 million more in ad revenue from Sochi than it generated from the 2010 Winter Olympics in Vancouver, British Columbia, which were hurt by the weak economy.

Winter said the stronger economy and higher prices were helping ad sales for Sochi. Advertisers, he said, also remain committed to big sporting events that draw huge audiences in this era of fragmented media and time-shifted TV viewing.

NBC attained its ad-sales goal even though two big advertisers, Anheuser-Busch and Hilton Worldwide, have not reserved advertising for the Sochi games.

Advertisers who have stepped forward include General Motors, Smucker's, Liberty Mutual, Coca-Cola, and AT&T.

Some believed the time difference of at least eight hours between Sochi and the United States would deter advertising sales in the lucrative prime-time slots on NBC. Most of the ad money is spent on the NBC broadcast-TV network in prime time.