Paul Cook is keen to bring in the attacking midfielder to bolster his bid to get out of League Two next season.
The 33-year-old has spent the past two campaigns with MK Dons.
Baker has scored 15 goals in 72 appearances for the club who were relegated from the Championship last season.
The Scouser started his career at Southport and has also had stints with Morecambe, Stockport and Coventry.
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Cook has recruited Matt Clarke and Danny Rose so far this summer with Adam Webster departing for Ipswich.