McLeod returned from a one-match ban to score a spectacular 61st minute scissor kick and a clinical lob, while Ashley Williams and Robert Clare saw red for County.
The fired-up Dons completely dominated the first half but Stockport defended superbly to ensure the game was goalless at the break.
McLeod fired just over from 25 yards after finding space on the edge of the box in the fifth minute, and the impressive Lloyd Dyer went close when he cut inside Keith Briggs down the left flank but his low right-foot drive was beaten out well by diving County goalkeeper James Spencer in the 21st minute.
The unmarked Aaron Wilbraham, returning to the strike-force for the dropped Clive Platt, should have scored moments later but he volleyed Paul Butler's precise knock-down wide from 10 yards.
At the other end, Stockport's only shot on target in the first half came from Stephen Gleeson, whose deflected 25-yard strike was saved comfortably by Dons keeper Lee Harper just before the half-hour mark.
County's Michael Rose then curled a 30-yard free-kick just over the bar after Sean O'Hanlon had been booked for obstructing Tes Bramble as he burst towards goal in the 40th minute.
But the Dons ended the first half on top and Wilbraham fired McLeod's pull-back inches wide from the edge of the box a minute later, before Dyer curled just over from 25 yards on the stroke of half-time.
The second half started in subdued fashion with both teams keen to give nothing away but Adam Proudlock tested Dons keeper Harper when he turned O'Hanlon 25 yards out and unleashed a low left-foot snap-shot.
But McLeod sparked the game into life when his spectacular scissor kick put the Dons ahead in the 61st minute.
Keith Andrews collected Jon-Paul McGovern's free-kick before drifting a cross to the back post and, after Williams had unconvincingly headed the ball up in the air, McLeod planted a magnificent overhead kick inside the far top corner from 10 yards.
David Poole went close to equalising for Stockport when he cut inside from the right but his low 20-yard left-foot strike was saved well by Harper, before Williams saw red in the 68th minute.
Williams was shown a straight red card for bringing down McLeod as he burst through on goal, but County protested vehemently as the Dons striker looked to have lost control of the ball.
McLeod scored his 13th goal of the season to double the Dons' lead in the 75th minute, coolly lobbing on-rushing County keeper Spencer from Dyer's throughball.
And Stockport's misery was compounded when Clare picked up his second booking for a silly handball on the halfway line in the 90th minute.