The Express & Star says manager Mick McCarthy made the latest Wolves check on the highly-rated 19-year-old in North End's 2-1 defeat at Reading on Tuesday night.
But Liverpool are also in the hunt, with Reds assistant manager Sammy Lee seen at Deepdale several times this season. Preston-born Barton is described as a ball-playing midfielder who likes to get forward.,
He has made 32 appearances for Preston this season, including 23 Championship starts in what is his first full campaign in senior football. Barton made his League debut a year ago tomorrow for Preston in a 3-2 win over Scunthorpe.