Jamie Walker gave Bradford the first-leg advantage over Carlisle following a 1-0 win in their Sky Bet League Two play-off semi-final.
The Scottish midfielder scored the only goal in a close encounter at Valley Parade – a game watched by the largest crowd at this stage in the fourth tier.
The 20,575 attendance saw Carlisle pile on the pressure in the second half but Mark Hughes’ Bradford held on to take a slender lead to Brunton Park next Saturday.
Just goal difference had separated the two sides in the final league table – and their previous encounters had produced only one goal.
The opening exchanges were predictably tight in a raucous atmosphere.
Ben Barclay’s header was saved by Bradford goalkeeper Harry Lewis and Joe Garner hit the bar, although play was pulled back for a handball against the Carlisle forward.
The home side went in front from the resulting free-kick, Alex Gilliead and Andy Cook heading on from Lewis’ long kick before Scott Banks played in Walker to fire past Carlisle’s Tomas Holy.
As Bradford maintained the pressure, Walker was close to a second as his cross-shot flashed across the Carlisle goal.
Owen Moxon’s set-piece delivery looked the best route back for Carlisle. Jack Armer headed wide from their first corner and Corey Whelan was also off target on the end of a Moxon free-kick.
Bradford had another chance in added time at the end of the half as Banks surged forward into the penalty area but Holy was out to narrow the angle and save his toe-poke shot.
Carlisle, who had won only one of their previous nine Valley Parade visits, pressed for a response early in the second half and Alfie McCalmont’s first-time volley was held by Lewis.
Adam Clayton then lost possession in Bradford’s half but Garner delayed in the corner of the penalty area, allowing Romoney Crichlow to steal the ball away.
Carlisle manager Paul Simpson swapped both strikers on 58 minutes to bring on Ryan Edmondson and Kristian Dennis.
Edmondson quickly won a corner but Barclay could not get a proper connection on his header.
Carlisle continued to enjoy the upper hand and their best chance fell to Edmondson after a mistake from Crichlow but he shot across the face of goal before Armer drove into the side-netting.
Edmondson’s aerial presence had given the visitors an attacking edge and he should have scored from Armer’s cross but he headed past the post with Lewis beaten and looked visibly annoyed with himself.
Bradford were hanging on as Dennis burst through but Lewis did enough to force him wide and he shot behind the goal.
Defeat meant Carlisle have won only two of their last 12 games but their strong second-half showing will give them hope for the return.