Sunderland earned the point they needed to secure top spot in Group F, and with it a home tie in the next round of the EFL Trophy.
Theo Robinson's goal gave Bradford a first-half lead, before Nathan Broadhead levelled just after half-time.
The draw meant the game went to a penalty shootout, and Bradford triumphed 4-2 but it mattered little with Sunderland already through and the Bantams already eliminated.
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Here's how James Hunter rated the Sunderland players.
Thorben Hoffmann 7
Made a series of saves to keep Sunderland in the game
Kenton Richardson 6
Did well defensively, and came close to scoring
Frederik Alves 6
Better in his natural position
Ollie Younger 6
Did OK alongside Alves
Lynden Gooch 5
Played at left-back and had a tough night, including a missed penalty in the shootout
Harrison Sohna 5
Too easily beaten for the goal
Luke O'Nien 6
A couple of decent passes to set Sunderland on the attack
Elliot Embleton 6
Excellent throughball for the equaliser
Alex Pritchard 6
Tried to create and he hit the bar right at the death, before missing in the shootout
Leon Dajaku 5
Had a couple of chances but was foiled by the keeper on both occasions
Nathan Broadhead 6
Scored the all-important goal before coming off shortly afterwards
Subs
Will Harris 6
For Broadhead 57mins. Should have scored, but a goalline clearance denied him
Ellis Taylor 6
For Embleton 73mins. Did OK
Carl Winchester 6
For Sohna 73mins. Fresh legs in the final 15 minutes
Not used: Burge, O'Brien, Wright, Dyce
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