Dale's challenge at the top end of League Two has been built on their success away from home, but they have won only once on home turf so far and were second best against the Shrimps. Morecambe let the hosts off the hook early on when Lewis Alessandra teed up Jack Redshaw, but the former Dale striker sent his shot wide of the upright.
But when an identical opportunity presented itself in the 10th minute, this time set up by Kevin Ellison, Redshaw made no mistake by sliding a neat finish past goalkeeper Josh Lillis.
Jim Bentley's side almost doubled the lead when Ellison's shot was deflected off Rhys Bennett onto the post. For Rochdale, Dele Adebola saw his powerful close-range header brilliantly saved by Barry Roche while Kevin McIntyre's cross-cum-shot looped over the keeper onto the crossbar.
Morecambe extended their lead midway through the second half when Redshaw converted Ellison's cross.
The hosts pulled one back when George Donnelly's header was deflected past Roche off Will Haining, but the visitors went close to a third when Haining's 30-yard free kick smacked the crossbar and they hung on for a deserved win.