Del. Alston indicates the referendum is letting her vote for SSM:

Accordingly, I have resolved that if and when the chairman calls the vote I will be ready to vote based on what I believe to be right.  In time the people of Maryland will also have the opportunity to vote on what they each believe is the correct direction for our State to take.  In the interim I hope and pray that you will all respect my vote although you may not agree with it. Thank you all for the privilege to serve as your Delegate." (source: Baltimore Sun)