Supreme Court Justice John Roberts engages in a spirited discussion with Edie Windsor's lawyer Roberta Kaplan during Wednesday's Defense of Marriage Act hearing.
The Supreme Court won't rule until June, but gay-marriage advocates said the justices' decision to tackle the issue has already helped them win a victory in the court of public opinion.
"The more and more the country talks about this issue, the more and more people come to our side," Michael Cole-Schwartz of the Human Rights Campaign said Wednesday after the high court heard two days of arguments on same-sex marriage cases.
A wave of senators — from Ohio Republican Rob Portman to Virginia Democrat Mark Warner — publicly backed marriage equality in the days before this week's back-to-back hearings.
Surveys show Americans increasingly support legalizing same-sex marriage. A Washington Post/ABC News poll found 58 percent of people in this country think it should be legal for gays and lesbians to tie the knot.
Joshua Roberts / Reuters
Supporters of gay marriage rally in front of the Supreme Court on March 27, 2013. Both sides are cautiously optimistic, but marriage-equality advocates say no matter what happens, they've won in the court of public opinion.
"I'm feeling enormously proud at the who's who of America that came before the court and the public to say it's time for the freedom to marry," said Evan Wolfson, founder of Freedom to Marry. "We know we have momentum and the winning strategy and we will see whether the court delivers in June."
Wolfson said he is cautiously optimistic the marriage-equality movement will notch gains when the Supreme Court issues its opinions on California's Proposition 8 and the federal Defense of Marriage Act, but he said activists aren't taking a wait-and-see approach.
Legislators in four states — Illinois, Minnesota, Rhode Island and Delaware — could vote on same-sex marriage measures even before the justices sign off on their opinions, and advocates are turning their attention from Washington to the statehouses.
The other side is also gearing up for the next round of political battles. Andrea Lafferty, president of the Traditional Values Coalition, said gay-marriage proponents may have underestimated their opponents' strength.
"I can't believe all the people who have called me who haven't been engaged before," she said. "I think they [marriage-equality advocates] might be surprised that they’ve awoken the sleeping giants."
The two camps were united in their reluctance to declare a win before the Supreme Court actually rules, even though the justices gave hints about their thinking.
NBC News Justice Correspondent Pete Williams reported Wednesday that the court signaled that it might narrowly strike down DOMA, which denies same-sex couples the same federal benefits as married heterosexuals.
The day before, after arguments on the Prop 8 ban on same-sex marriage, the justices hinted that a sweeping ruling knocking out such state laws isn't in the cards.
"I was in the courtroom both days and I think the court was clearly trying to find a solution that did not require imposing same-sex marriage on all 50 states," said John Eastman of the National Organization for Marriage, which opposes same-sex marriage.
He predicted the justices will uphold Prop 8 and "let the issue continue to play out in the political process," with states deciding whether to permit gay marriage.
On the DOMA case, Eastman said he's optimistic the federal law will survive while conceding the argument it impinges on states' right to regulate marriage got some "traction."
But Wolfson read the tea leaves differently: "I think we are going to see rulings that one way or another will continue moving the country in the direction of the freedom to marry.'
The Rev. Rob Schenck of the Evangelical Church Alliance said after Wednesday's hearing that he believes DOMA and the federal definition of marriage as between one man and one woman is "at great risk."
"If that should happen, we have urged in our brief that this court take into consideration and explicitly guarantee the religious freedom of military chaplains, civilian chaplains, as well as other clergy who are required by law to swear an oath to serve the Constitution," he said.