The survey finds that income level and religious convictions were bigger factors than race or age. According to the survey found 63 percent of those making less than $40,000 a year voted for the ban, and 85 percent of evangelical Christians also voted yes on Prop 8.
Among other religious groups, 66 percent of Protestants supported the ban, along with 60 percent of Roman Catholics.
The poll found that 56 percent of those over age 55 also voted yes on Prop 8, and 57 percent of nonwhite voters.
But the Public Policy Institute of California says only 48 percent of voters in the Nov. 4 election said they opposed the idea of making gay marriage legal. Forty-seven percent of the poll's roughly 2,000 participants said they support legalizing gay marriage while 5 percent were undecided.
The Associated Press contributed to this story.
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