Matt Polster gave the hosts a tenth-minute lead before Paxton Aaronsen leveled with his first goal for Philadelphia.
The difference in the match was a 39th-minute strike by Gustavo Bou that gives the Revolution a ten-point lead atop the Eastern Conference standings.
Story of the match
Philadelphia had the first chance of the match as Aaronsen forced a turnover with the ball landing at the feet of Leon Flach. He flicked a pass to Sergio Santos, who saw his shot stopped by goalkeeper Matt Turner.
New England then created their first chance of the game and scored on it. Tommy McNamara made a quick pass to Polster and he curled his shot past goalkeeper Andre Blake and into the back post to make it 1-0.
Aaronsen then collected a pass from Jakob Glesnes and made a quick move to his left past Andrew Farrell and rifled a shot into the upper corner, leaving Turner with no chance to equalize.
The decisive moment came six minutes later as Flach fouled Tajon Buchanan. Bou stepped up and took the penalty, which was saved by Blake, but he left a rebound that Bou pounced on to deposit.
They nearly had a third as Quinn Sullivan lost an aerial duel with the Revolution pouncing on the loose ball, Blake saving a close-range shot. The hosts failed to capitalize on a good chance from a subsequent free-kick.
Miscommunication gave New England another good chance in the 71st minute as Adam Buksa latched onto a pass and faked left, but Glesnes wasn't fooled and blocked the shot relatively comfortably. Blake again saved from close range ten minutes from time.
A lovely sequence led to Daniel Gazdag passing to All-Star Kai Wagner, who sent the ball into the path of Kacper Przybylko, but the Pole slightly mistimed his volley. The Union were nearly level in stoppage time after Wagner's shot hit the post.
That was the final chance of a spirited contest as Philadelphia turns their attention to a CONCACAF Champions League semifinal against Mexican powerhouse Club America on Wednesday.
Man of the match: Matt Turner
For all of the talk of New England's potent offense with Bou and Carles Gil, Turner has been a vital contributor to the Revolution's success and he made several key saves that helped his side take all three points.