Overnight leaders Slough Town suffered a 4-1 defeat at a Basingstoke Town side who are now ninth.
In front of a crowd of just under 600 at the Camrose, Lewis Putman gave the Rebels a 22nd minute lead. But three minutes after the break, Aaron Jarvis equalised and then Slough had Mark Nisbet sent-off on 55 minutes.
Nana Owusu on 62 minutes, Jarvis again three minutes later and Aaron Redford in stoppage time added further goals to inflict Slough`s first defeat since August 9.
Leamington's fifth successive league win, courtesy of Ryan Rowe`s 65th minute effort at third-bottom St Neots Town saw them move a point clear of Slough at the summit.
Chippenham Town, Hitchin Town and Dunstable Town complete the top five – with the latter losing at Creasey Park to Chippenham, whose David Pratt after five minutes and Andy Sandell after 21 minutes, gave them a cushion that Danny Green cut on the half-hour mark. But the Duns were unable to find a leveller.
Hitchin were comfortable 4-1 Top Field winners against a now fourth-bottom St Ives Town.
Danny Webb and Will Wright had the Canaries two-up at the break. Dubi Ogbonna reduced the arrears after 64 minutes but a Robbie Burns brace in the 70th and 81st minutes sealed Hitchin`s win.
Merthyr Town are just a point behind Dunstable in sixth after Kayne McLaggon`s 22nd minute strike eventually proved enough to see off Biggleswade Town at Penydarren Park.
Redditch United are seventh after sharing a 0-0 draw at the Avenue Stadium with Dorchester Town while Kettering Town`s poor home run finally came to an end as they beat old rivals Weymouth 3-1.
A crowd of 542 saw Bradley Tarbuck give the Terras a 13th minute lead – a lead they held until the midway point of the second half when Aaron O`Connor equalised. Skipper and long-server Brett Solkhon then gave the Poppies an 85th minute lead that Liam Canavan stretched four minutes into stoppage time.
Second-bottom Cambridge City shared a 1-1 home draw with Kings Langley, whose Kane Pope cancelled out new boy Ben Robinson`s 10th minute opener for City on the half-hour mark.
Cinderford Town remain rooted to the bottom after Drew Roberts` 42nd minute penalty eventually proved enough for visiting Chesham United.
Elsewhere, Ciencester Town moved out of the bottom four after sharing a 1-1 draw at Hayes & Yeading United, whose Olumide Durojaiye gave them the lead right on half-time, only for Aidan Bennett to level on 65 minutes.
Frome Town had a good 2-1 win at the Spencer Stadium against Banbury United.
Ricky Johnson gave the Puritans a 21st minute lead but Dan Cleverley levelled 10 minutes after the break and then Corby Moore won it for the Somerset side on 69 minutes.
Richard Gregory broke the deadlock at Stratford Town to give the home side a 58th minute lead that Lee Stevenson cancelled out for King`s Lynn Town 10 minutes later.
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