Members of Philadelphia's largest transit union and the Southeastern Pennsylvania Transportation Authority are set to vote on a contract to end the strike that has idled buses, subways and trolleys for five days.

Negotiators for Transport Workers Union Local 234 and SEPTA tentatively agreed on a proposed contract late Friday night. Both sides will vote on the proposal at 2 p.m. Saturday.

Gov. Ed Rendell said Friday night that he is optimistic that the trains and buses will be running by Saturday evening.

The union walked out early Tuesday in a dispute largely centered on pension benefits. SEPTA's regional railroad has been running during the strike because those workers are represented by a different union.