Fifty-two percent of Americans favour the US Government recognizing same-sex marriages, with 42 percent opposed, a new poll showed.

The finding from the Public Religion Research Institute was released just days before the US Supreme Court hears oral arguments in two landmark cases involving marriage equality next week.

“We have reached a tipping point on the issue of same-sex marriage in the country, fueled primarily by overwhelming support among younger Americans, but also by broader shifts in opinion,” PRRI’s Chief Executive Robert Jones said in a statement.

“Even among constituencies that have historically been most opposed to same-sex marriage (such as evangelical Protestants), younger members now support it.”

Same-sex marriage now is legal in nine states and the District of Columbia home to the US capital Washington. The Federal Government’s refusal to recognize those marriages is a key issue facing the Supreme Court justices on Tuesday and Wednesday.

Previous polls have shown growing acceptance of marriage equality among Americans, with a Washington Post-ABC survey earlier this week putting support at 58 percent, an all-time high.

Another poll out Friday, from the Gallup Organization, indicated 54 percent of Americans would support giving married gay and lesbian civil servants the same rights and benefits as their heterosexual counterparts.

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