Three:
One to write the light bulb removal program,
one to write the light bulb insertion program, and
one to act as a light bulb administrator to make sure nobody else tries to change the light bulb at the same time.
or
Because all his other wives support Hillary.
or
No one knows. Republicans automatically disbelieve him, and no one can ever trust a stinking liberal anyway.
or
Because there's no one else to wag it for him.
or