The 28-year-old is hot property in the second tier having scored 16 goals and laid on 11 assists last season, with Sheffield United and Derby having also been linked.
However, with Boro now cash-rich following the sales of Ben Gibson and Patrick Bamford, the club have cash on the hip and appear to have won the race for his signature.
North east-born Waghorn will now discuss personal terms with Boro, who are thought to be hopeful of completing the deal in time for him to feature against Sheffield United on Tuesday night at the Riverside.
Derby's attempts to add to their squad have been hampered by their precarious situation regarding Financial Fair Play, with Matej Vydra still expected to move on before the deadline after seeing a move to Leeds collapse.
Waghorn was left out of the Ipswich side that drew 2-2 with newly-promoted Blackburn in their Championship opener on Saturday.
Middlesbrough are desperate for additions in the attacking third, with Bamford having left, Adama Traore expected to leave and Rudy Gestede currently out injured.