Promotion hopefuls Wolves dropped two important points as the early dismissal of striker Nathan Blake proved costly.
Blake was shown the red card after just 14 minutes for an apparent elbow on Millers defender Shaun Barker.
Despite their numerical disadvantage, Wolvess created the bulk of the goalscoring opportunities and even had a late penalty but Colin Cameron's spot-kick was saved by Michael Pollitt.
But with Ipswich and Norwich losing, sixth-placed Wolves actually strengthened their grip on a play-off place.
Dave Jones' side threatened first with Blake's right-footed shot being turned behind for a corner by Pollitt after seven minutes.
Wolves were then dealt a hammer blow when Blake was dismissed.
The 31-year-old appeared to elbow Barker in the area and after consulting his linesman, the referee produced a straight red card.
Winger Mark Kennedy dribbled a left-footed shot wide before Lee Naylor drilled in a 25-yard effort which was held by Pollitt.
Rotherham were forced into a change on the half hour as injured striker Richie Barker was replaced by Darren Byfield.
Cameron was booked for a foul on Millers midfielder Gareth Farrelly before Pollitt tipped Shaun Newton's overhead kick over the crossbar just before the interval.
Rotherham showed more attacking intent at the beginning of the second period and John Mullin had an effort blocked by Naylor after 50 minutes.
Millers midfielder Curtis Woodhouse, back in the side after a hamstring injury, was booked for a foul on Cameron before Alan Lee headed a good opportunity wide for the visitors.
Paul Ince was replaced by Alex Rae on the hour before Scotland international Kenny Miller, who has been in superb form recently, was also taken off with George Ndah his replacement after a month's absence.
The striker almost broke the deadlock after 75 minutes when his header was brilliantly parried by Pollitt and Newton smashed the rebound over the crossbar.
Cameron had a shot superbly saved by Pollitt and the goalkeeper's then kept out the Scotland international's penalty with just three minutes remaining after substitute Dean Sturridge was brought down.
Wolverhampton: Murray, Irwin, Lescott, Butler, Naylor, Newton,
Cameron, Ince, Kennedy, Blake, Miller. Subs: Oakes, Ndah, Clyde,
Rotherham: Pollitt, Daws, Shaun Barker, Swailes, Hurst,
Sedgwick, Mullin, Woodhouse, Farrelly, Lee, Richard Barker.
Subs: Gray, Byfield, Warne, Talbot, Hudson.
Referee: A Hall (West Midlands)