Aleksandar Mitrovic could have been dismissed for two yellow cards inside the first half-hour, but he remained on the pitch to condemn Wolves to another defeat at Molineux.
Helder Costa curled a free kick over for Wolves before Nouha Dicko volleyed wide at the back post, but their best opportunity fell to Richard Stearman, who sent the ball over the crossbar from close range after meeting Danny Batth's flick on.
However, just before the half-hour mark, Newcastle should have been reduced to 10 men after Mitrovic went in late on Ikeme, but the referee decided against handing him a second yellow card.
It was a let-off which came back to hurt Wolves and after Mohamed Diame had earlier seen a header stopped from finding the corner, Mitrovic gave the Magpies the lead.
After Diame's volley had been blocked, Newcastle kept the ball alive and a neat flick from Jamaal Lascelles set up Mitrovic to score from close range.
Soon after the restart, Wolves came agonisingly close to finding an equaliser but Dave Edwards was only able to glance his header into the side-netting after meeting Costa's cross.
However, after that opening, the home side struggled to create anything significant in the final third, and Newcastle were equally ineffective at the other end after replacing Mitrovic at half time.
Diame sent a tame effort into the hands of Ikeme with five minutes to go, before Costa did the same down the other end to force Karl Darlow into his first save of the night.
Wolves mounted a late assault on the Newcastle goal but they could not create another opening and Newcastle were able to hold on for a crucial three points, which takes them one point above Brighton & Hove Albion.