NEWS ---Reluctant, justices hear arguments over same-sex marriage

As partisans argued pointedly over same-sex marriage outside the U.S. Supreme Court building, either hoping for or dreading a landmark decision, justices inside seemed reluctant to extend a sweeping constitutional right for gays and lesbian to wed in all 50 states.

In the first of two days of hearings on cases that have the potential to fundamentally alter how American law treats marriage, Justice Anthony Kennedy -- considered the likely deciding vote on the divided court -- questioned whether the case even belonged before the court.

"This was a deeply divided Supreme Court, and a court that seemed almost to be groping for an answer here," said CNN Senior Legal Analyst Jeffrey Toobin, who watched the arguments.

On the point of allowing same-sex marriage in California, Justice Elena Kagan, a liberal member of the court, asked, "What harm is there to the institution of marriage?"

But more conservative members of the court took a go-slow approach. Justice Samuel Alito said the law on same-sex marriage is too new.

"There isn't a lot of data on its effect" on children and the institution of marriage, he said.

The 80 minutes of arguments Tuesday on California's Proposition 8 ban on same-sex marriages will be followed Wednesday by arguments on the federal Defense of Marriage Act, a 1996 law that defines marriage as between a man and a woman.

Supporters of same-sex marriage rallied outside the Supreme Court, hoping justices would reach for a broad ruling that would strike down bans nationwide.

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"We are not asking for anything more than our neighbors, friends and family, but certainly expect no less," said Todd Bluntworth, who spoke with his husband and their two children to a crowd of supporters hoping for a historic ruling from the Supreme Court striking down laws banning same-sex marriage.

But opponents urged the court to keep out of the issue and leave the decision to states.

"If you want to get married, go to one of the states that allows gay marriage," said Carl Boyd Jr., a conservative Nashville talk-show host. "Stop trying to force your agenda down our throats. Quit trying to bully the American people with the homosexual agenda."

Some demonstrators carried sign reading "Kids do best with a mom & dad."