Sheffield Wednesday, Blackburn Rovers and Hull City all won at home to boost their play-off chances, while Bristol City earned a key victory away to Fulham.
Under-fire Middlesbrough boss Jonathan Woodgate saw his team collect a precious three points at home to Charlton Athletic and Stoke City's misery continued with a defeat at the KC Stadium.
West Brom, now second, can bounce back above Leeds when its hosts Swansea City on Monday.
LEEDS MARCH ON
Marcelo Bielsa's men have won six in a row, conceding just twice in that run, after easing to victory in a Yorkshire derby away to the struggling Terriers.
Second-half goals from Ezgjan Alioski and Pablo Hernandez saw the new leaders continue their momentum against a Huddersfield team now without a win in five league games.
The play-off picture is still typically congested but Wednesday jumped to sixth spot thanks to a 2-1 home win against fellow hopefuls Brentford, who led at Hillsborough thanks to Bryan Mbeumo.
Steven Fletcher struck twice as Garry Monk's Owls came from behind to secure successive wins after their previous run of five Championship matches without a victory.
Preston North End dropped out of the top six after losing 2-0 away to QPR, for whom Eberechi Eze scored both goals.
JOHNSON'S CHARGES END FULHAM RUN
Fulham had won four straight league games but missed the chance to exert pressure on the top two as a late fightback was not enough to avoid a home defeat against Bristol City.
Goals from Josh Brownhill and Famara Diedhiou had Lee Johnson's men in control at Craven Cottage but substitute Aboubakar Kamara struck to set up a grandstand finish.
The Robins held firm despite nine added minutes being played and they moved fourth, level on points with third-placed Fulham, ahead of successive home games.
Lee Tomlin's injury-time goal earned Cardiff City a 3-2 win at home to rock-bottom Barnsley, the Bluebirds' third straight victory moving them up to eighth, only a point behind Wednesday.
A fourth consecutive win for Blackburn was secured by Adam Armstrong, a 1-0 defeat at Ewood Park meaning Derby County have taken only four points from their past five league games.
MUCH-NEEDED WIN FOR BORO
Middlesbrough are up to 19th, easing the pressure on hometown hero Woodgate, after a 1-0 win against Charlton at the Riverside.
George Saville scored with 52 seconds on the clock and Boro held on to secure back-to-back 1-0 home victories to move four points clear of the bottom three.
The big game in the battle for survival saw Luton Town host Wigan Athletic and it was Graeme Jones' side who came out on top, bouncing back from a 7-0 thrashing at Brentford last time out.
Wigan led through Kieffer Moore but a chaotic finale left the Latics in the bottom three, Callum McManaman levelling for Luton with three minutes of normal time to play.
Cheyenne Dunkley was shown a second yellow card in added time and the Hatters made the 10 men pay as George Moncur scored from a corner to complete a stunning late comeback.
Stoke slipped to a 2-1 defeat at Hull despite Sam Vokes opening the scoring, with Jarrod Bowen's brace taking his Championship tally to 14 for the season.