Punjab's latest win took them to 22 points, four ahead of second-placed Kolkata Knight Riders, who will be their opponents in Qualifier 1.
Both teams will have two bites of the cherry, with the winner directly making it to the final while the loser will take on the winners of the Eliminator.
Daredevils, with their ninth consecutive loss, ended the Indian Premier League (IPL) seventh season without a win on Indian soil. Their two solitary wins in 14 matches came in the UAE leg. They failed to register a win in nine matches in India.
Captain Kevin Pietersen's 58 off 41 balls was the saving grace for Delhi Daredevils as another poor showing with the bat saw them being shot out for 115 runs in 18.1.
Such was the dismal performance by the Daredevils that barring Pietersen, Dinesh Karthik (13) and Jimmy Neesham (12), the rest of the batsman failed to even reach double figures.
Parvinder Awana, Akshar Patel, Mitchell Johnson and Karanveer Singh took two wickets each while Rishi Dhawan chipped in with one.
In reply, Kings XI strolled to their 11th win of the campaign with Manan Vohra (47) and David Miller (47 not out) stringing together a 96-run third wicket stand off just 60 balls that helped them reach 119 for three in 13.5 overs.
Kings XI's chase, though, got off on a disastrous note. Virender Sehwag (7) and Glenn Maxwell (0) were both dismissed early, giving Delhi a bit of a chance.
At 16 for two, Pietersen would have hoped for a couple of more quick wickets to really put some pressure on their opponents.
Vohra led a stunning counter-attack that saw him smash four boundaries and two sixes. Miller, initially, played the perfect sheet anchor role before flexing his muscles as the target neared.
The South African batsman who has been a key component of the Punjab juggernaut hit four fours and cleared the boundary twice.
Delhi's bowling again lacked the penetrating power with the spinners going for plenty. However, left-arm pacer Jaydev Unadkat bowled brilliantly giving away just three runs and picking up a wicket from his two overs.
Delhi Daredevils: 115 all out in 18.1 overs (Kevin Pietersen 58, Dinesh Karthik 13; Parvinder Awana 2-15, Karanveer Singh 2-22).
Kings XI Punjab: 119 for three in 13.5 overs (Manan Vohra 47, David Miller 47 not out; Jaydev Unadkat 1-3, Mohammed Shami 1-26)