I don't know much about the Marines, but I can add that my sister inlaws brother was a pilot for one of the air force one helicopters while Clinton was President.
Yea that would be known as Marine Helicopter Squadron 1. Or HMX-1. The helo that flies the President is known as Marine 1. Nothing to do with the Air Force. They have the H-3, and H-60 that actually flies the president. That is known as the White Side. Then you have the Green Side which flies CH-46s and CH-53s.