League One leaders Cardiff held off a Bradford fightback to win 2-1 at Valley Parade.
Brian Barry-Murphy was named manager of the month for December and his side marked that achievement by moving nine points clear of the third-placed Bantams.
David Turnbull tested Bradford keeper Sam Walker with a deflected shot and then beat him with a well-placed curling finish from 20 yards to give Cardiff a 14th-minute lead with his first league goal of the season.
Alex Robertson and Ryan Wintle drove over the bar before Cardiff added a second 10 minutes later. Ollie Tanner’s shot through a crowded box was flicked home by captain Calum Chambers, the former Arsenal defender’s second goal in consecutive appearances.
Bradford began to find their stride before half-time with Josh Neufville, Bobby Pointon and Curtis Tilt all putting efforts wide.
Stephen Humphrys skied a big chance to pull one back from six yards out after good work by Neufville.
Jenson Metcalfe gave the hosts hope after 59 minutes with a similar shot to Turnbull’s into the top corner from outside the box. But Cardiff kept Bradford at bay to record their sixth away win of the league season.