ANNAPOLIS, Md. (AP) — Baltimore’s Cardinal Edwin O’Brien says he is not surprised by the state Senate’s approval of gay marriage, but that the move threatens families.

The Senate approved a bill to allow same-sex unions Thursday evening, setting Maryland up to be the eighth state to legalize same-sex unions when Gov. Martin O’Malley signs the bill next week.

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O’Brien issued a release later Thursday saying neither the church nor government should be able to redefine marriage, a common cry among opponents of the legislation.

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O’Brien pledged that the Baltimore Archdiocese will work to overturn the law.

Opponents have vowed to bring the legislation to referendum on the November ballot. They will need to collect more than 55,000 valid signatures from Maryland voters to do so.

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