Josh Huggins gave second-placed Boro the lead six minutes before the break at Thame. Experienced forward Dennis Oli then made sure with a second with 10 minutes remaining.
Neighbours Kempston Rovers, Barton Rovers and AFC Dunstable occupy the remaining top five slots, with Marlow slipping out after losing 2-1 at Sharpenhoe Road to Barton.
It was goalless until the 66th minute when Michael Malcolm gave Rovers the lead that Connor Calcutt swiftly doubled two minutes later. Chris Ovenden replied from the penalty spot 12 minutes from time for which Dan Hutchins received a straight red card but the hosts held on to move above their visitors.
Kempston had to make do with a point from a 3-3 thriller at Honeycroft against Uxbridge.
However, considering they were trailing until the last minute, the Walnut Boys will be grateful for one point. But they were 2-0 up with goals from top scorer Danny Watson after 21 minutes and Ashley Fuller 11 minutes later.
The Reds turned that round to lead 3-2 with goals from Abobaker Eisa from the spot six minutes after the interval, Tayo Davies Coker on 64 minutes and Matty Woods three minutes later. Sam Johnson popped up with the Walnut Boys` last-gasp leveller.
AFC Dunstable moved into the top five after beating second-bottom Petersfield Town 3-1 at Creasey Park.
Jermaine Hall bagged a brace either side of the half-time break. Will Essai gave Town hope of a comeback with an 85th minute reply, but BJ Christie ensured the points stayed at home with a third two minutes into stoppage time.
Potters Bar Town are seventh, just two points behind the top five, after a 3-1 home win over surprise third-bottom outfit Aylesbury FC.
The Moles took an early seventh minute lead through Alan Musoke. But Eoin Casey and then Chris Doyle responded either side of the break to give the Scholars the lead and Ashley Nathaniel-George made sure with a third 16 minutes from time.
Bottom-markers Histon lost again and are now sixteen points adrift of Aylesbury.
Ashford Town (Middx) won 4-1 at the Glassworld Stadium with goals from Dan Fleming after nine minutes, Tom Brunton seven minutes later, Bayley Mummery 10 minutes before the break and Kameron English after 67 minutes – Joe Peacock replying from the spot nine minutes from time.
Beaconsfield SYCOB moved three further points clear of the bottom two after a 3-0 Holloways Park win over Arlesey Town in which Charlie Losasso bagged a brace in the 10th and 42nd minutes and Aaron Berry the third right on half-time.
Elsewhere, Pat Cox was another to net a brace as Fleet Town edged out Chalfont St Peter 3-2, despite the Saints leading 2-0 inside eight minutes through Adam Kirby and a Craig Davis own goal. Rob Carr scored the home side`s third on 64 minutes.
Hanwell Town enjoyed a similar scoreline at home to Bedford Town, this time Dean Allen their two-goal man either side of a Zak Joseph effort after 38 minutes. The Eagles replied through Andrew Phillips and Devante Stanley within two minutes of each other midway through the second half.
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