The 24-year old former Arabs star is back at Tannadice on a six-month loan from Blackburn Rovers and Thompson is excited about seeing him in a tangerine shirt under manager Jackie McNamara.
"Our season-ticket sales are 1200 down on this time last year," he said.
"But David's return sends out a message to the fans that we're serious about making an impact next season.
"I want the supporters, in return, to come out and back the club. Every team needs the backing of its supporters and there's a lot of youthful talent being assembled here.
"Goodwillie is only 24 but will be one of our senior players when the season starts."
He added: "Jackie said he wanted a proven goalscorer. I said to him: 'Do you fancy trying to get Goodwillie back?' and he said: 'Absolutely.'
"There were times when I thought it was never going to happen but this deal hasn't been done for the sake of it.
"Now he has come back at a time when this club's going down a different route. I mean no disrespect to anyone when I say we are getting a younger, and hungrier, group and looking to explore their potential."