Dude, while I do think I seen a site claiming a different origin for the red suit, it is not from the poem "T'was the night before christmas". It states quite clearly "He was dressed all in fur, from his head to his foot,
And his clothes were all tarnished with ashes and soot;" it goes on to describe his red nose and cheeks, but that is it. You did not get red fur back then and their is nothing in that to suggest a red cloth suite trimmed with fur like we have today.
Now of course I have to go look up where it really started because I am sure Coca Cola stole it from somewhere!