Sheffield Wednesday have had an approach turned down, while Preston North End say they have been priced out of the market.
Wharton says 'four or five' clubs have expressed an interest in the striker, who netted a club record 32 goals for the Iron this term.
"They all know what our asking price is. It is £2m plus other extras which could bring us substantially more," Wharton told the Scunthorpe Telegraph.