The answer is, he probably won't have to. The definitive social issue of our time may have no political consequences for Christie now, tomorrow, or ever.
First and foremost, this may no longer even be an issue by the November gubernatorial election, let alone the 2016 presidential race.
New Jersey courts could legalize gay marriage as soon as next month. If that happens - and Christie is obligated by law to comply - then done is done. State Sen. Barbara Buono (D., Middlesex), Christie's opponent, can make the argument all she wants that Christie is "denigrating and demeaning and marginalizing our gay and lesbian brothers and sisters," as she did last week. But will that statement have currency among voters when pictures show the opposite, of men marrying men and women marrying women at town halls across New Jersey?
If, on the other hand, a New Jersey judge rules against gay marriage, the Legislature could vote to override Christie's 2012 veto. But advocates and legislators suggest that such an override - which would require 15 additional votes - would not likely happen until the lame-duck session after the November election. So any such high-profile legislative denouncement of Christie's social conservatism would have no bearing on his reelection.
By 2016, this issue could join Prohibition in the graveyard of social issues battled and buried. Now that the Supreme Court has effectively decided the issue on the federal level, presidential candidates may not have to answer as many questions about it. Christie already has the veto on his resumé, which Santorum-grade conservatives will appreciate, and it is unclear how many pro-gay-marriage voters would punish him for a fight they would already have won.
Even if the social revolution surrounding this issue galvanizes voters' interest this year, there is little evidence to indicate that pro-Christie New Jerseyans care where he stands on any issue, let alone this one. Most New Jerseyans disagree with Christie on abortion, polls show, and many think he hasn't done a good job handling rising property taxes and the economy. But every survey finds his home-state voters really, really like him as a person. And, after Sandy, they trust his leadership. That's why he's up at least 30 points over Buono in the polls.
"His principal appeal is still him, rather than any specific policy, and how he does as an executive in a vague sense, whether it's Sandy or the budget," said Julian Zelizer, a Princeton University political historian.
Christie's positions on gay issues are also nuanced enough to give most people a little something they can live with.
He is the single reason gay marriage does not exist in New Jersey - that's probably good enough for most conservatives.
At the same time, Christie has said he believes gay people are born gay. He has said that although he is Roman Catholic, he does not think gays are sinners. And when he vetoed the gay marriage bill in February 2012, he sent a provision back to the Legislature that would create an ombudsman to make sure couples in civil unions are treated fairly.
He also wants a gay-marriage referendum and said he would abide by whatever voters decided. But Democrats don't want to do that, saying votes should not be held on civil rights. And pollster Patrick Murray of Monmouth University says that's good news for Christie.
If a gay marriage question is not on the same ballot as Christie's name in November, "it doesn't change any political dynamic here in New Jersey," Murray said.
Democrats flatly deny their push for gay marriage has anything to do with politics. When a persistent TV reporter pressed the Democrats last week about how gay marriage would help them in the election, Buono was Christie-like in her response: "I don't even know how you can ask that."
She then apologized (un-Christie-like). But in an e-mail the following day to supporters, Buono wrote: "New Jersey is a solidly blue state with Democratic values but Chris Christie has somehow disguised himself as a moderate and we have to work together to expose the truth. . . . A perfect example of Christie's presidential politics vs. New Jersey is his adamant stance against marriage equality."
So, she hopes, if marriage equality won't get her the votes she needs, maybe using the issue to reveal Christie's unbridled, aggressive, rightward ambition will.
Contact Matt Katz at 609-217- 8355, email@example.com, or follow @mattkatz00 on Twitter. Read his blog, "Christie Chronicles," at www.inquirer.com/ christiechronicles.