Washington (CNN) -- A majority of justices raised questions in oral arguments Wednesday about the federal Defense of Marriage Act, indicating the Supreme Court may strike down a key part of the law that denies legally married same-sex couples the same benefits provided to heterosexual spouses. A ruling is expected within three months on the constitutionality of the 1996 law that defines marriage for federal purposes as only between one man and one woman. Wednesday's arguments concluded two days of presentations before the high court on one of the most prevalent social issues of this era -- the right of gay and lesbian couples to wed and receive the full benefits of law provided to heterosexual couples.
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NEW: "I think it's gonna be good," says Edith Windsor, the focus of the DOMA challenge
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The court appears divided on the questions of discrimination and state authority
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Justice Anthony Kennedy refers to states' "power to regulate marriage"
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The Defense of Marriage Act denies benefits to same-sex couples
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