RNZI reports Leicester's lead over Spurs increased to eight points with four games remaining. The in-form Londoners play tomorrow at home to West Bromwich Albion.
And it was a doubly dismal day for Arsenal, after the Gunners were held to a scoreless draw at Sunderland.
That enabled the Black Cats to claw their way back up to 17th, and put Norwich back down in the relegation zone.
Shorn of the attacking talents of the suspended England striker Jamie Vardy, Argentina's Leonardo Ulloa scored a double to help the Foxes outclass the visiting Welsh side at a delirious King Power Stadium.
Leicester are in touching distance of a fairytale first-ever top-flight English football title now, and it never really looked in doubt once Ashley Williams' careless clearance after 10 minutes gifted Riyad Mahrez his 17th goal of the season.
The Foxes' dream of completing their surreal journey from 5,000-1 no-hopers to English champions felt more tantalisingly real once Ulloa took centre stage.
He headed home the second goal on the half-hour and tapped in a third on the hour as the Foxes cruised while their fans merrily sang: "Are you watching, Tottenham?"
The Spurs faithful who were watching could only sigh as substitute Marc Albrighton smashed in a fourth in the dying minutes to confirm Leicester's eight-point lead over the second-placed Londoners.
Should Tottenham lose their game in hand at home to West Bromwich Albion on Tuesday, Leicester, who need five points from their last three games to take the title, could even be crowned champions next Monday with victory at Manchester United.