Goals from Dan Schiavi, David Burton-Jones, Scott Coupland and Charlie Coulson secured the home success as Deeping made it 12 games without defeat.
Whitworth took the local bragging rights and moved to within a point of second-placed Olney Town as they beat Raunds Town 3-0 in Division One.
Jack Dyson opened the scoring for the Flourmen and a second-half double from Remy Brittain completed a fine victory.
Irchester United made it two wins in a row and moved into the top 10 with an impressive 3-2 success at Melton Town.
Ty Clark scored twice and Sam Dengel was also on target while goals from Steve Truman and Aiden Black were in vain for the hosts.
Jed Ainge scored a late penalty to rescue a point for Rushden & Higham United as they drew 4-4 with Bourne Town at Hayden Road.
The Lankies looked to be on course for a victory when Jake Reynolds Ryan Kalla and Ainge put them 3-0 up.
But Bourne turned it around thanks to a Tom Cardall hat-trick and a Craig Rook goal before Ainge’s late spot-kick ensured honours ended even.
Thrapston Town twice fought back to draw 2-2 with Long Buckby at Chancery Lane.
Manny Salumu gave the visitors the lead before Jedd Whiteman levelled just before the break.
Salumu scored again for Buckby but Mason Thomas struck to earn the hosts a share of the spoils.
Rothwell Corinthians’ Buildbase FA Vase second-round clash with Tring Athletic fell foul of the weather with the Sergeants Lawn pitch being waterlogged after the heavy rain.
The two teams will try again on Tuesday night.