Both groups are ready to meet club owner Mike Ashley’s £280million asking price.
Reports suggest they could take control of the club in early 2009.
Seymour Pierce is the broker who are selling the club.
Keith Harris, the chairman of Seymour Pierce, said: “It is a good estimate to say the club will be sold by January.
“There is serious interest expressed by two parties and work is going on with them. One group approached me and I approached one group.
“The change in the level of the dollar versus sterling has made it much more attractive to buy sterling assets at this time.
“The new owner wants to be in a position to make an assessment of what adjustments need to be made in January.”
Ashley bought the club for £134million, 18 months ago.
