The Nomads also have a game still in hand, after completing a league double over Briton Ferry Llansawel.
Having already won 3-0 in the reverse fixture in south Wales, the Nomads followed up with an entertaining 4-2 victory at Deeside Stadium.
The win strengthened their grip on second place, opening up a four-point cushion over third-placed Penybont, while defeat proved costly for Andy Dyer’s side as Briton Ferry slipped into the relegation zone.
Harry Franklin was the standout performer for the home side, taking his tally for the campaign to 14 goals in all competitions with strikes either side of the interval.
It was the visitors, though, who struck first when Tom Walters put Briton Ferry ahead in the 34th minute.
The lead did not last long, with Franklin restoring parity just five minutes later to ensure the teams went in level at the break.
The Nomads wasted no time after the restart. Within a minute of the second half kicking off, Callum West found the net after being released by Franklin to give the hosts the lead.
Briton Ferry responded positively and were back on terms in the 54th minute when Ollie Anderson finished well to make it 2-2.
From that point on, momentum shifted decisively in favour of the home side.
Dyer was shown a yellow card on the sidelines in the 73rd minute as frustration grew for the visitors.
Ten minutes later Max Woodcock edged Connah’s Quay back in front, and matters worsened for Briton Ferry when Tom Price was dismissed late on after receiving a second yellow card.
Franklin then put the seal on an impressive afternoon, scoring again in the fourth minute of stoppage time to wrap up the points.
“Today we’ve cemented our spot in the top six, that’s all we were looking to do at the start of the season,” said Nomads boss John Disney.
Elsewhere, Haverfordwest County produced a dramatic late comeback to snatch a point in a 2-2 draw away to fellow relegation battlers Flint Town United.
Flint appeared to be cruising to victory when they entered the final 10 minutes with a two-goal advantage, only for their lead to evaporate in the space of two minutes.
The dropped points denied the Silkmen the chance to climb three places in the table.
With three matches remaining in Phase 1, Flint remain just one place off the bottom and firmly entrenched in the fight to avoid relegation.
Haverfordwest, meanwhile, will take encouragement from their late rally but remain very much involved in the same battle.
The draw was County’s fifth of the season and followed on from their 2-0 win at Bala Town, meaning they have collected three points from a possible six this month ahead of festive fixtures against bottom club Llanelli Town on Boxing Day and Cardiff Met on 30 December.
Flint had looked comfortable for long periods. Elliot Reeves scored his 11th league goal of the campaign in the 35th minute to give the hosts a deserved 1-0 lead at the interval.
That advantage was doubled in the 63rd minute when Joshua Jones converted from the penalty spot, sparking hopes of an early Christmas boost for the home supporters.
However, Haverfordwest refused to lie down. Dan Hawkins pulled one back in the 84th minute to give the visitors belief, and just a minute later Ben Ahmun struck his eighth goal of the season to level the scores.
Both sides pushed for a late winner, but neither could find a decisive breakthrough as the contest ended all square.
