Joy at last for Rangers
Goals from Steven Davis and Sone Aluko put Rangers two ahead inside 16 minutes and Andrew Little justified his selection up front with a composed finish.
Steve Williams headed one back before the break but Lee McCulloch netted an opportunistic fourth.
Rangers remain 20 points behind Celtic though after Gary Hooper’s second-half strike proved enough to see off third-placed Motherwell at Parkhead.
Pat Fenlon’s Hibernian moved three points clear of Dunfermline at the bottom with a 3-1 win over Kilmarnock at Rugby Park.
Tom Soares scored twice with former Cork City hitman Roy O’Donovan getting the other.
Irish striker Jon Daly was among the scorers as Dundee United leapfrogged Hearts into fifth by beating them 2-0 at Tynecastle.