Le Toux scored on a penalty kick in the 80th minute to pull the Union (8-7-1) within a goal, then tied it in the first minute of stoppage time. Roger Torres also scored for the Union.
Philadelphia has a seven-match winless streak (0-3-4) and hasn't won since July 17 in a 3-0 victory at New England.
Rajko Lekic, A.J. Soares, Moncef Zerka and Benny Feilhaber scored for the Revolution (4-11-12). They have a seven-game winless streak (0-2-5).
Philadelphia was without Faryd Mondragon, the All-Star goalkeeper who fractured his right ring finger in last Saturday in a 2-1 loss at Real Salt Lake. Rookie Zac MacMath made his first career start for the Union.
This game was originally scheduled Aug. 28, but was moved because of Hurricane Irene.