"We're hoping that will get us a nice wave from him and we'll get some people singing along with us, " says McGowan, who served in the Marines from 1964-68, including a tour in Vietnam.

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People watching from the public gallery and some lawmakers immediately broke into song, singing the New Zealand love song "Pokarekare Ana", AP news agency reported.

BBC: New Zealand legalises same-sex marriage

Some people might find it odd if Sherrie, played by Julianne Hough, was sitting on a bus singing and nobody around her seemed to notice, Viagas said.

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