Chris Dagnall gave Keith Hill’s men an early lead when he turned in Chris O’Grady’s cross in the ninth minute.
Former Dale man Adam Le Fondre went close twice with a low shot pushed round the post by Frank Fielding and a brave diving header cleared off the line by Craig Dawson.
But Dale doubled their lead in the 64th minute when O’Grady held off two markers before slamming a low cross into the six-yard area where Rotherham’s Jamie Green inadvertently turned the ball past his own goalkeeper.
The result was tied up in the 71st minute when Dawson rose highest in a packed penalty area to head Ciaran Toner’s corner past the hapless Warrington.
Man of the match O’Grady deservedly added his name to the scoresheet three minutes later with a cool finish.