The Bristol Evening Post reports that their sources claim City manager Derek McInnes is keen to bring in Wootton on loan until the end of the season.
City face competition from Blackburn Rovers who are also keen on signing the former Liverpool player.
Wootton joined United from rivals Liverpool at the age of 15.
“I wasn’t too sure whether I was going to sign (for Liverpool),” Wootton later told the Daily Mail.
“United invited me down for a week’s trial and said they wanted to sign straight after that. It was really good.”