Washington approved Referendum 71 this past November, giving domestic partners in the state nearly all the rights of married couples. Since then, the amount of new domestic partnership registrations has doubled each week.

This is no surprise, as Joshua Friedes from Equal Rights Washington explained to a local news organization:

I think we’re seeing these large numbers of people registering, even though it’s not full marriage equality, because of the incredible breath of protection families are getting through the system.

Legal benefits hav long encourage opposite sex couples to get married, and those same benefits (at least, for now, on the state level) encourage same sex couples too.