Nobody really was a direct "winner" stemming from the victory of Proposition 8. Gays and lesbians obviously lost. Anyone who knows and cares about gays and lesbians lost too. Everyone else is a wash, as their marriages are in roughly the same shape that they were a week ago.
But apparently, someone may have gotten a big boost from Prop. 8's passage, almost by accident: Mitt Romney. Recall that Romney's bid this time around was derailed in part by social conservatives who simply did not trust that he was "one of them" -- in part, it must be said, because Romney was actually rather socially moderate until approximately five days before he began his presidential campaign, but certainly in part because there is a lingering mistrust about Mormonism from within the conservative Christian community. But now Marc Ambinder notes that the LDS has purchased significant social conservative credibility due to its role in getting Proposition 8 passed -- credibility that will only be strengthened as the forces of godlessness, paganism, and equality continue to train their fire on the church.
Best of all for Romney, this occurs nearly entirely under the table. The only tangible impact is a lessening of suspicion conservative Christians have towards him on account of his Mormonism. He never took a front-line position on Proposition 8, and thus will see no more liberal backlash due to his anti-equality position than any other similarly situated Republican.
Romney's keeping his toes in the political water, and probably will run again in 2012. With the unabashed support of the Christian right, his candidacy will be far more formidable.