The vote follows a bitter dispute that has seen Screen Actors Guild members fighting among themselves and left further behind than they started.
Ballots must be received by 5 p.m. (8 p.m. EDT) and will be counted shortly afterward.
Hollywood actors seem split on the deal, while those based in New York are largely in favor. The outcome could depend the vast majority of members who are mostly actors without work.
Either result would have little short-term effect, because actors have continued to work under their old, expired contract. But a rejection of the contract risks driving the union into irrelevance, as TV networks turn to a smaller actors union, AFTRA.
Copyright 2009 The Associated Press.
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