Arbroath won at Clyde, Elgin City beat visitors Edinburgh City and Annan Athletic hammered Stirling Albion.
And Montrose's 2-1 win over Berwick Rangers to move above Clyde in fifth.
Shane Sutherland got a hat-trick in Elgin's 3-1 defeat of Edinburgh, while Smart Osadolor and Max Wright each scored twice for Annan.
At Station Park, Cowden's Dale Carrick put the visitors ahead, but Josh Peters brought Forfar level after the break.
And Thomas O'Brien and Lewis Milne netted to secure a 3-1 win for the hosts.
Colin Hamilton put Arbroath ahead away to Clyde only for Peter MacDonald to equalise.
However, the Bully Wee went down to 10 men when Ryan Finnie received a second booking and Ricky Little's free-kick made it 2-1 to Arbroath.
Sutherland scored twice for Elgin before Craig Beattie pulled one back for Edinburgh and completed his treble from the penalty spot.
Stirling led against Annan through Blair Henderson, but Osadolor scored either side of half-time and Wright added two more for the Galabankies to round off a 4-1 victory.
Montrose trailed against Berwick early in the second half as Michael McKenna scored, but the hosts levelled through Chris Templeman and Ryan Ferguson netted the winner.
Forfar Athletic came from behind to beat bottom side Cowdenbeath and remain eight points clear at the top of Scottish League Two.