The Academy of Motion Pictures Arts and Sciences announced a new voting procedure on Tuesday for the best picture Oscar nominees.
The preferential voting system, in which Academy voters will rank their favourites in order of preference, is designed to accommodate the increase in best film nominees from five to 10 that was announced earlier this year.
"Instead of just marking an X to indicate which one picture they believe to be the best, members will indicate their second, third and further preferences as well," Academy president Tom Sherak said.
He explained that the method would prevent a film being named a winner despite having just slightly more than 580 votes out of a total voting pool of 5,800 members. The new method, he said, would "establish the best picture recipient with the strongest support of a majority of our electorate".
The Academy hasn't used a preferential voting system since 1945, two years after the field of best picture nominees was reduced from 10 to five. Voting in all other Oscar categories will remain unchanged.
According to the Hollywood Reporter, the new rules will create a new challenge for Oscar campaigners, who will now have to concentrate on amassing as much wide support as they can, rather than simply building a critical mass of number one votes.