Donors gave more than $83 million to support or oppose the ballot initiative that abolished same-sex marriage in California.
New campaign disclosure reports made public Monday cover the weeks immediately before and after the Nov. 4 election.
They show that elected officials, businesses, churches and individuals poured millions more into the contest than previously reported.
The final tallies show that at year's end, opponents of Proposition 8 had raised $43.3 million and had a little more than $730,000 left on hand.
The measure's sponsors raised $39.9 million and had $983,000 left over.
Even before the late contributions were added up, the race already had become the most expensive ballot measure on a social issue in the nation's history.
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To see all the people who donated money to or against Proposition 8, click here.