At a damp Apperley Bridge training ground, James struck twice after the restart to build on an interval lead given to City by goals from Christopher Routis and Dylan Mottley-Henry.
The only downside for the Bantams was the sight of Josh Morris limping off towards the end of the first period after the midfielder went down hurt under a Wrexham challenge.
For Morris, the game was his first competitive fixture of any kind since the middle of September after injuring his knee at Fleetwood Town.
Up until his early departure, Morris had looked bright having been involved in a number of promising City attacks.
Morris actually played his part in City's opener on 18 minutes when his corner delivery was knocked down by Alex Laird and Routis crashed home into the roof of the net from close range.
Morris had three efforts on goal himself later in the half, with James also warming the 'keeper's gloves with a shot of his own just after the half hour mark, before City doubled their lead through Mottley-Henry.
The pacey winger managed to shrug off the attentions of a Wrexham defender ten minutes before the break to latch onto James' lofted pass and stride for the box.
With Wrexham's 'keeper off his line and closing him down, Mottley-Henry took control of the situation to expertly lob the ball over the shot-stopper's head from the edge of the box for City's second.
Mottley-Henry turned provider shortly after the break for City's third when he teed up James to fire into the far bottom corner with a low angled drive from just inside the box.
Apprentice winger Ellis Hudson, who replaced Morris shortly before the interval, then set James for his second of the match in the 66th minute.
Receiving Hudson's low cross to feet, James struck for goal and his drive took a sizeable deflection off a Wrexham defender to wrong-foot the 'keeper and find the net.
James was substituted directly before the restart after the goal for Niah Payne, whilst Routis received 73 minutes under his belt before he was replaced by Xander McBurnie.
CITY XI
1. Joe Cracknell
2. Kwame Boateng
3. Luca Mellor
4. Christopher Routis
5. Alex Laird
6. Kesi Omolokun
7. Dylan Mottley-Henry
8. Danny Devine
9. Luke James
10. Sumaili Cissa
11. Josh Morris
Substitutes:
12. Chandler Hallwood
14. Xander McBurnie
15. Ellis Hudson
16. Niah Payne
Substitutions:
Hudson for Morris (43), Payne for James (67), McBurnie for Routis (73)