All five council Democrats support the plan, on which a final vote is expected next Monday or Tuesday. All four Republican members oppose the proposal that would expand the county's existing ordinance banning discrimination based on sexual orientation.
The proposal also aims to protect gays, lesbians and transgender people should a statewide referendum be successful in overturning a recent gay-rights state law.
"It is important for us here in King County to make a statement of support for the sexual-minority community," Democratic Council member Dow Constantine told the Seattle Times.
Republican Council member Reagan Dunn said such an ordinance would strain small businesses and open the door to lawsuits.
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