Swansea climbed to third in the Sky Bet Championship after they beat Sheffield Wednesday 2-0 at Hillsborough.
Wednesday manager Darren Moore, returning to the touchline, made three changes to the side that lost to QPR at the weekend. Keiren Westwood was preferred to Joe Wildsmith in goal, Liam Shaw replaced Osaze Urhogdhide and Joey Pelupessy came in for Callum Paterson.
Cooper's Swansea line-up was unchanged from the team that beat Millwall on Saturday.
Shaw forced Freddie Woodman into action shortly before the half-hour mark. Racing on to Adam Reach's pass, the defensive midfielder looked to pick out the top corner but was denied by an acrobatic stop.
Lowe broke the deadlock in the 31st minute with his third goal in two games. Ayew muscled Julian Borner off the ball and squared a pass across the face of goal for Lowe to tap in his 13th goal of the season.
Wednesday's Josh Windass was denied by a last-gasp tackle from Ryan Bennett shortly after the restart, while at the other end, Ayew was denied by Westwood after dinking the ball neatly over his marker.
Cooper made his first substitution in the 73rd minute as Connor Roberts replaced Routledge and it proved to be an inspired move as Roberts created the second goal for Fulton, who steered a bullet header past Westwood 60 seconds later.
The Welshman raced onto a through ball and picked out Fulton, who sealed a second consecutive away victory for Swansea.