Serge Aurier's miscued cross and Son Heung-min's late effort proved enough to lift Mauricio Pochettino's men back above Burnley.
Though Spurs were far from the five-star best they had shown against Stoke City at the weekend, Liverpool and Arsenal's goalless draws against West Brom and West Ham respectively leave the result with a brighter look.
Erik Lamela's return to the Spurs XI for the first time in over a year ruined by hip injuries was a further boost for the home fans at Wembley.
Tomer Hemed had Brighton's clearest chance after 70 minutes, but his effort on the turn failed to stretch Hugo Lloris, who spent most of the contest as a spectator.
Brighton have collected just two points from their last six league games and are beginning to look over their shoulder, with just a three-point cushion over the relegation zone.
Making his first start in almost 14 months, Lamela was charged with replacing the creativity of Dele Alli, but the Argentine blazed over as finding a way through the well-drilled Brighton defence proved difficult, with Harry Kane barely given a sniff.
Lloris went untested until Shane Duffy forced him into a comfortable save after 35 minutes with a towering header from Anthony Knockaert's corner.
It was a fleeting attacking moment for the visitors and Spurs finally found a way through five minutes before the break, albeit with a huge slice of fortune.
Aurier – under a challenge from Jose Izquierdo – mishit a deep cross into the penalty area that caught Mat Ryan out, the ball looping over the goalkeeper to give the Ivorian his first Spurs goal.
Tottenham's dominance continued after the restart and Kane was denied by Ryan, stretching out his left boot to deny the England international's deflected shot.
With 20 minutes remaining the hosts' frustrations were beginning to grow and Hemed almost snatched a point, but his snapshot was straight at Lloris, much to the relief of the Spurs captain.
Pochettino introduced Alli for Lamela after 74 minutes and he almost had an immediate impact, setting up Kane for a curling shot that Ryan got down well to save.
Kane's personal duel with Ryan had one final chapter as the striker's low free-kick was superbly pushed onto the upright, but the Australian could do nothing to stop Son's front-post header that deflected off Davy Propper on its way in as Spurs finally earned the sheen their supremacy deserved.