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Volunteers at a Colorado Air Force base monitoring maps showing Santa Claus' progress are several hours into their goodwill mission and have answered more than 41,000 phone calls from people asking about the jolly old elf.
Phones have been ringing nonstop Monday at Peterson Air Force Base, headquarters of the North American Aerospace Command's annual Santa-tracking operation.
As of 7 p.m. -- more than 4-billion presents have been delivered.
Dozens of helpers at NORAD are taking calls and tracking Santa's location on large projection screens. They're posting updates for nearly 1.2 million Facebook fans and 104,000 Twitter followers.
The volunteers started taking calls at 4 a.m. Mountain time and will keep updating until 3 a.m. on Christmas morning.
