I think that's an unfair assessment. I remember discussing with him his winning the election, and how surprised he was by not only the amount of liberal support he had, but also by the surprising amount of votes he had in areas he spent no time or money campaigning.
That said, your comment made me curious so I dug a little and found an interview in the Seattle Gay News. He clearly states he would have sided with the majority in the Anderson case which upheld DOMA constitutionality. Not exactly "pro-homosexual marriage".
It also seems more likely it was Sander's propensity for siding with criminal defendants that did him in.
The media intentionally misconstrued his position regarding the rights of criminal defendants, even though I thought he went too far in a number of cases. Primarily, he simply wanted the prosecutors to do their jobs the way it is supposed to be done and not take shortcuts by denying the constitutional rights of an accused; which is a huge problem with prosecutors and judges in the State of Washington.
The media's hatred of him was only because he was pro-DOMA. Wiggins had the strong support of the homosexual community. I don't care what Wiggins said in an interview, just you watch how he votes on those cases.