SEATTLE (CBS Seattle) - The Washington state House of Representatives will vote Wednesday on the gay marriage bill that cleared the Senate 28-21 last week.

The House is expected to endorse the bill and that would move the state another step closer to becoming the seventh to recognize same-sex marriage.

Most of the support for the bill comes from Democrats who control both legislative bodies.

If the bill passes the House vote, it will then go to Governor Christine Gregoire. She would then have five days to sign it into law.

According to Reuters, opponents of same-sex marriage said they would seek to overturn the legislation via one of two ballot measures: a referendum for repeal or an initiative defining marriage as the exclusive domain of heterosexual couples.

Six other states already recognize same-sex marriage — New York, Massachusetts, Connecticut, Vermont, New Hampshire and Iowa – as does the District of Columbia.

Maryland, New Jersey and Maine are also close to being added to that list.

On Tuesday, a federal appeals court declared a voter-passed ban on same-sex marriages in California, Proposition 8, to be unconstitutional.