It moved them clear at the top because Huddersfield were held to a 1-1 draw by bottom club Swindon.
Chris Brandon equalised for the Terriers after Andrew Gurney had put the Robins ahead with a first-half penalty.
Lee Trundle, who recently signed a David Beckham-esque image rights deal, also claimed a matchball after inspiring Swansea to a 5-1 success over Chesterfield.
Adebayo Akinfenwa and Owain Tudur-Jones also got on the scoresheet for the Swans, with Steve Blatherwick getting the consolation for the visitors.
Brentford failed to take advantage of Huddersfield's slip, as they lost 2-0 at home to Bournemouth - with James Keene and James Hayter getting the goals.
Former Iron striker Paul Hayes helped Barnsley move to fifth with the opening goal in a 2-1 win over 10-man Walsall at Oakwell.
The win keeps the Yorkshire side above his former club, who beat Oldham 4-2, on goal difference.
Port Vale slipped away from the play-off spots after losing 2-1 at home to Hartlepool United - with Eifion Williams (12) and Thomas Butler (64) scoring either side of Michael Cummins' (43) effort.
Nottingham Forest edged past Bradford thanks to an early goal from David Johnson.
Colchester put clear distance between themselves and the relegation zone with a last-gasp goal from Chris Iwelumo sealing a 3-2 win over Yeovil.
Pablo Bastianini had put Yeovil ahead only for Iwelumo to equalise, with Matt
Harrol putting the Glovers back ahead before Jamie Cureton got a second leveller to set up the late drama.
Tranmere climbed out of the relegation zone with a 2-0 win at Doncaster, with Steve Davies and Steven Jennings getting the second-half goals.
Gillingham also pulled themselves out of the drop zone by beating Blackpool at Priestfield - former Iron captain Chris Hope levelled Keigan Parker's operner, with Neil Harris getting the winner.
Seasiders goalscorer Parker was later shown a straight red card for violent conduct.
MK Dons remain second bottom of the league, despite Malvin Kamara's late goal earning a point at home to Rotherham - for whome Andy Monkhouse had scored.