Gay-rights opponents predict that a ruling from the Massachusetts high court barring out-of-state same-sex couples from marrying here could reinvigorate efforts in a handful of states that do not expressly prohibit such marriages. Mathew Staver, president of Liberty Counsel, a conservative legal group based in Florida, said the high court's ruling could strengthen opposition in states that now do not have either a law or a constitutional amendment banning same-sex marriage. "I think that was already in process, but I think that this was just an extra impetus for a state to get a Defense of Marriage Act or a...