There are three factors that determine if your home is a marketable listing - price, financing, and time.
Price - If your home is priced too high, you must be willing to wait much longer for your home to sell. Either it will take that much longer to find someone to pay more than the home is worth, or the real estate market will eventually catch up to the "asking price" of the home through inflation.
After deciding on a price, try the old retail trick - drop the amount down a bit. Instead of placing the listing at $140,000, consider dropping it down to $139,990.
Financing - You may not realize it, but the buyers' financing abilities can have a tremendous impact on the successful sale of your home. Try to offer very attractive financing options. Consider carrying the financing yourself at a below-market interest rate or preparing your home for government financing. This could open the door for many Buyers who otherwise could not consider your home.
Time - If time is important to you, then you must be willing to lower the price.