The Tigers claimed a fifth consecutive victory on Saturday afternoon, taking full advantage of nearest rivals Peterborough United's inactivity and another defeat for third-placed Lincoln.
And, although they have played three games more than Posh and two more than the Imps, Grant McCann's men's hopes of securing automatic promotion now rest in their own hands with 10 matches of the season remaining.
Visiting Oxford certainly played their part in what was an absorbing contest and, with less than a minute on the clock, Dan Agyei showed good pace to run in behind and get on the end of a long clearance before forcing Matt Ingram into an early save.
Agyei then produced an inviting low cross from the left that was begging to be finished off, but evaded everyone inside the Hull box.
Having engineered several promising situations of their own without managing to really extend visiting custodian Jack Stevens, City would break the deadlock on 22 minutes.
Lewis-Potter had looked their brightest attacking threat during the opening stages, and it came as no real surprise that it was he who put the Tigers in front.
Lewie Coyle's nicely-weighted switch from right to left released the 20-year-old winger, who cut inside and onto his right foot to curl a low finish around Stevens and into the far corner of the United net.
The end-to-end nature of the match continued, with Mark Sykes testing Ingram before Cameron Brannagan smashed the rebound high over the cross-bar.
Hull's goalkeeper then pulled off an even better save, diving low to his right to claw away Josh Ruffels' downward header from Anthony Forde's right-wing centre.
Yet, for all their positive play, Oxford almost found themselves two goals down just before the interval, Lewis-Potter taking aim from 25 yards out with a beautifully-struck effort which had the beating of Stevens, but just slightly too much on it.
The second period was a similarly close affair, with both sides playing some decent football.
It was Hull who looked the more likely to get the game's all-important next goal, as they repeatedly caught their visitors out on the counter-attack.
Gavin Whyte's deflected strike from inside the box forced Stevens to parry, then, after dispossessing Ruffels near halfway, the City winger broke down the right before sliding Mallik Wilks in behind.
But, having danced around Stevens, the hosts' top-scorer ran out of room and the ball ran harmlessly out of play.
Honeyman then led a break out of defence from an Oxford corner and looked set to play Callum Elder clean through, only for a crucial intervention from a retreating defender to rescue the Yellows.
No matter, McCann's men would eventually double their advantage on 71 minutes.
And it was Lewis-Potter who once again did the damage, raiding down the left at pace, shifting the ball onto his right foot as he approached the penalty area and seeing his goal-bound shot deflected past Stevens by Rob Atkinson.
Hull lost skipper Coyle to a nasty-looking head injury not long after going 2-0 up, but saw out the closing stages comfortably, continuing to get themselves into some decent positions while United toiled away without any success at the opposite end of the field.
Hull City: Ingram; Coyle (Emmanuel 82), Burke, Greaves, Elder; Docherty, Jones, Honeyman; Whyte (Crowley 77), Wilks, Lewis-Potter (Magennis 73). Unused substitutes: Long, Eaves, Scott, Slater.
Oxford United: Stevens; Forde, Moore, Atkinson, Ruffels; Brannigan, Lee (Taylor 73), Hason, Shodipo; Sykes (Barker 56), Agyei. Unused substitutes: Eastwood, Gorrin, Hall, Grayson, Kelly.
Referee: A Backhouse (Carlisle).