After both teams' opening possessions ended in punts, the Steelers had to settle for a field goal to open the scoring, with Chris Boswell converting from 44 yards out.
The Seahawks forced a turnover when they spotted a fake field goal attempt by Pittsburgh, with backup quarterback Landry Jones attempting to complete a pass on fourth down, giving Jeremy Lane the interception.
Lane stumbled on the return while looking for the touchdown, but the home side were able to get the ball into the endzone a couple of plays later when Russell Wilson connected with a wide-open Baldwin.
It did not take Pittsburgh long to restore their lead as Heath Miller and DeAngelo Williams both moved the chains to get the visitors back down the other end of the field, leaving Martavis Bryant to run in from 11 yards out.
The lead changed hands again before half time though, with Williams powering his way over for the touchdown, before Roethlisberger fired the ball to Jesse James for a two-point conversion.
Pittsburgh looked to extend their lead further at the start of the third quarter, but the visitors had to send Boswell on for the field goal when the drive stalled.
The Seahawks struggled to find their rhythm after the break, punting three times in the third quarter before Ahtyba Rubin intercepted a Roethlisberger pass, bringing the Seattle offense back onto the field.
Graham made a one-handed diving catch at the one-yard line, leaving Rawls to run the ball over on the next play, but the home side remained a point adrift after Steven Hauschka's extra point was blocked.
Richard Sherman secured his first interception of the season as Roethlisberger tried to get the ball to Antonio Brown, resulting in Wilson picking out Kearse for his second touchdown of the game a couple of plays later.
The Steelers soon regained the lead though, as Markus Wheaton hauled in a 69-yard catch from Roethlisberger just 37 seconds after Rawls's effort, but the two-point conversion attempt was intercepted by Sherman.
Seattle came back on the field looking for a fifth touchdown, with Tyler Lockett and Baldwin both making big gains before the latter found the endzone for his second touchdown.
The Pittsburgh offense returned looking for another touchdown to move ahead yet again, but the drive stalled as Bryant dropped a catch before Roethlisberger came up short running for the endzone, forcing Boswell to kick a field goal, which left the visitors two behind.
The Steelers almost forced a turnover as Seattle tried to see the win out, but Rawls was able to recover the ball after Wilson fumbled the snap.
The quarterback made amends on the next play, launching a deep pass to Baldwin, who dodged a couple of tackles before running from the halfway line for his third touchdown of the game, leaving the Steelers needing to score twice in the final two minutes, and giving Wilson five touchdown passes in a game for the first time in his career.
Jones took over from Roethlisberger under center for the AFC North side, handing the ball off to Williams for a first down, but Kam Chancellor made an interception for the Seahawks to prevent Pittsburgh getting back into the game.
The result leaves both sides with 6-5 records, and leaves the Seahawks in a wildcard playoff place in the NFC, while the Steelers remain in the playoff hunt in the AFC.