Back in 2004, Oregonians approved that marriage would involve only one man and one woman.
Many states have since ruled in court these bans are unconstitutional.
Judge Michael McShane of Eugene is expected to rule soon on Oregon.
Peter Zuckerman with Oregon United for Marriage says there's been exponential change on this issue in recent years.
"Our country has really been on a journey of understanding. For me that's treating people how you want to be treated. We really should have the freedom to marry who they love. I'm looking forward to the day we win. No one should be told its illegal to marry the person they love."
It is unclear when the judge will make his ruling, but lawyers for Oregon United or Marriage has asked for a 24 hour heads up before the ruling is released.