City created just one clear cut chance and only poor finishing by Stockport prevented the visitors going home with a victory.
Stockport threatened after just two minutes when Liam Dickinson looked set to get clear, only for Lee Beevers to handle on the edge of his own box.
The free-kick from Anthony Pilkington was charged down but the Hatters kept pushing forward.
In the 14th minute a low cross from Dickinson was fumbled by City keeper Alan Marriott but the follow-up from Tony Dinning was saved.
Lincoln almost sneaked in front in the 18th minute when a header from Jamie Forrester was aimed at the top corner, only for Wayne Hennessey to produce a diving save.
But both teams plans were disrupted 11 minutes later. Lincoln's Nat Brown was fouled by Dickinson and reacted by kicking out at the Stockport man.
Dickinson then appeared to headbutt Brown and when referee Keith Hill finally restored order both men were shown a straight red card.
Stockport then had the better of things but their finishing was poor. Anthony Elding got clear in the 45th minute but shot across the face of the goal.
Then David Poole broke away down the right but with three team-mates unmarked in the middle he chose to go it alone and shot into the sidenetting.
Stockport almost took the lead in the 68th minute when an inswinging corner from Adam Griffin beat Marriott, but Scott Kerr headed off the line.
Three minutes from the end a great ball from Adam Proudlock set up Elding, only for Lincoln sub Paul Mayo to make a vital interception.