The pageant is to take place Nov. 9 at Crocus City Hall. It is to air on NBC with a Spanish simulcast on Telemundo.
Roberts is host of "MSNBC Live" and a contributor to "Morning Joe" and "Today."
Mel B. is a former member of the Spice Girls and was a judge on "America's Got Talent." She was host of the Miss Universe competition when it was held in Vietnam in 2008.
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