Confusingly enough probably not. Our governor signed the marriage act into law without it being on the ballot for public vote (correctly in my opinion). Referendum 74 was started as a way to force a public vote on the matter. The people who started it clearly think/want the public to reject the law. I am somewhat nervous about the vote as outside the King county area (Seattle, Redmond, etc...) the state can trend fairly conservative. So them fighting the referendum would mean fighting against putting this up for a public vote and fighting for leaving the law in place as it is.

Edit: for more clarity in last sentence.

That's what they meant. A yes vote on Ref 74 will legalize same-sex marriage.