CENTENNIAL, CO - AUGUST 21: Members of a hazardous materials team wear protective suits as they head into Republican presidenti
Date: 22/08/2008
CENTENNIAL, CO - AUGUST 21: Members of a hazardous materials team wear protective suits as they head into Republican presidential candidate John McCains campaign office August 21, 2008 in Centennial, Colorado. A threatening letter containing white powder was received at the suburban Denver office, prompting several workers to go to a hospital on their own, though no injuries were reported. (Photo by John Moore/Getty Images)
CENTENNIAL, CO - AUGUST 21: Members of a hazardous materials team wear protective suits as they prepare to head into Republican
Date: 22/08/2008
CENTENNIAL, CO - AUGUST 21: Members of a hazardous materials team wear protective suits as they prepare to head into Republican presidential candidate John McCains campaign office August 21, 2008 in Centennial, Colorado. A threatening letter containing white powder was received at the suburban Denver office, prompting several workers to go to a hospital on their own, though no injuries were reported. (Photo by John Moore/Getty Images)
CENTENNIAL, CO - AUGUST 21: Emergency response officers stage outside of presumptive Republican presidential nominee Sen. John
Date: 22/08/2008
CENTENNIAL, CO - AUGUST 21: Emergency response officers stage outside of presumptive Republican presidential nominee Sen. John McCains (R-AZ) campaign offices August 21, 2008 in Centennial, Colorado. Several people working in the office were hospitalized and released after a letter was sent to the office that contained a white powder. (Photo by Chip Somodevilla/Getty Images)
CENTENNIAL, CO - AUGUST 21: Cones warning of hazardous materials in the area stand outside of presumptive Republican presidenti
Date: 22/08/2008
CENTENNIAL, CO - AUGUST 21: Cones warning of hazardous materials in the area stand outside of presumptive Republican presidential nominee Sen. John McCains (R-AZ) campaign offices August 21, 2008 in Centennial, Colorado. Several people working in the office were hospitalized and released after a letter was sent to the office that contained a white powder. (Photo by Chip Somodevilla/Getty Images)
CENTENNIAL, CO - AUGUST 21: Members of a hazardous materials team put on protective suits as they prepare to head into Republic
Date: 22/08/2008
CENTENNIAL, CO - AUGUST 21: Members of a hazardous materials team put on protective suits as they prepare to head into Republican presidential candidate John McCains campaign office August 21, 2008 in Centennial, Colorado. A threatening letter containing white powder was received at the suburban Denver office, prompting several workers to go to a hospital on their own, though no injuries were reported. (Photo by John Moore/Getty Images)
CENTENNIAL, CO - AUGUST 21: Emergency response officers stage outside of presumptive Republican presidential nominee Sen. John
Date: 22/08/2008
CENTENNIAL, CO - AUGUST 21: Emergency response officers stage outside of presumptive Republican presidential nominee Sen. John McCains (R-AZ) campaign offices August 21, 2008 in Centennial, Colorado. Several people working in the office were hospitalized and released after a letter was sent to the office that contained a white powder. (Photo by Chip Somodevilla/Getty Images)
CENTENNIAL, CO - AUGUST 21: Members of a hazardous materials team put on protective suits as they prepare to head into presumpt
Date: 22/08/2008
CENTENNIAL, CO - AUGUST 21: Members of a hazardous materials team put on protective suits as they prepare to head into presumptive Republican presidential nominee Sen. John McCains (R-AZ) campaign offices August 21, 2008 in Centennial, Colorado. Several people working in the office were hospitalized and released after a letter was sent to the office that contained a white powder. (Photo by Chip Somodevilla/Getty Images)
CENTENNIAL, CO - AUGUST 21: Members of the U.S. Army National Guard 8th Civil Support Unit stage outside Republican presidentia
Date: 22/08/2008
CENTENNIAL, CO - AUGUST 21: Members of the U.S. Army National Guard 8th Civil Support Unit stage outside Republican presidential candidate John McCains campaign offices August 21, 2008 in Centennial, Colorado. A threatening letter containing white powder was received at the suburban Denver office, prompting several workers to go to a hospital on their own, though no injuries were reported. (Photo by John Moore/Getty Images)
