Nigel Pearson's men went into their game at mid-table Bournemouth knowing they had the opportunity to move further clear of QPR and Burnley, who battled out a 3-3 draw in the day’s early kick-off.
And veteran striker Kevin Phillips' 81st-minute goal, which came shortly after he was brought off the bench, ensured Leicester would collect all three points at the Goldsands Stadium and leave Bournemouth in 14th place.
That result came after Leicester's closest challengers had served up a thriller at Loftus Road.
Striker Kevin Doyle, who joined QPR on loan from Wolves on Thursday, opened the scoring after just seven minutes, but Burnley's Danny Ings equalised in superb fashion midway through the first half.
Richard Dunne restored the hosts lead before the interval, but a quick-fire double from Sam Vokes put Burnley ahead with 28 minutes remaining.
However, another QPR loan signing, West Ham's Modibo Maiga, came off the bench to grab a share of the spoils for Harry Redknapp's men late on.
Fourth-placed Derby County, meanwhile, missed the chance to move above Burnley into third as they were involved in a 3-3 draw of their own at Birmingham City.
Steve McClaren's side were in firm control after coming from a goal down to lead 3-1, but Birmingham claimed a point thanks to Chris Burke and a last-gasp equaliser from Manchester United loanee Federico Macheda.
Leeds United put their off-the-pitch turmoil to one side by coming from behind to post a 5-1 hammering of Yorkshire neighbours Huddersfield Town at Elland Road.
The Championship's top scorer Ross McCormack led the rout, weighing in with a hat-trick to take his tally to 21 goals for the season, as Leeds ended a seven-game winless run in the league.
In-form Reading - who have lost just one of their last six league games - consolidated their place in the play-off zone with a convincing 3-0 win at Millwall, while Ipswich Town remain four points adrift of Nigel Adkins' team after their 1-0 win over Bolton Wanderers.
At the wrong end of the table, second-bottom Barnsley were left heartbroken in their own Yorkshire derby as a 97th-minute winner from Chris Maguire gave Sheffield Wednesday - who are now unbeaten in seven Championship outings - all three points at Hillsborough.
Charlton Athletic remain in the relegation zone after slumping to a third straight league defeat with a 2-1 reverse at Wigan Athletic, who move up to 10th courtesy of two goals in the last two minutes from Marc-Antoine Fortune and Jordi Gomez.
Elsewhere, Blackpool made it 12 Championship games without a victory by going down 2-0 at Blackburn Rovers, while Middlesbrough recorded their second consecutive 0-0 draw with a stalemate at Doncaster Rovers.