The result has seen Neal Ardley's side open up a two-point gap at the top of the standings.
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The hosts took the lead with eight minutes on the clock as Jack Midson netted his eighth goal of the season.
The Port Vale comeback started a minute before the break thanks to debutant Daniel Jones's low strike from the edge of the area.
The visitors secured themselves a share of the points on the hour as Tom Pope capitalised on a weak back-pass to slot in.