Marian Hossa and Ben Smith also scored for the defending Stanley Cup champions, who have won three in a row and can wrap up the first-round series at home Sunday. Four of the first five games in the series have gone to overtime.
All three of the Blues' home games went to overtime and St. Louis won the first two. Toews got behind the St. Louis defence on the winner and threw a couple of fakes at Ryan Miller before slipping the puck past the goalie.
FLYERS 2, RANGERS 1
Ray Emery started the first three games for Mason, who was out with an upper-body injury. Mason played the final 7:15 in a 4-1 loss Tuesday night.
Dominic Moore scored for the Rangers.
Game 5 is Sunday in New York.