Casting a vote is read as making your choice count. In dreams a polling station points to a decision in your life and to the wish to have a say in what happens around you.
Has this come up in your dreams before? What was going on in your life then?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.