This question was sent by a reader a few days ago. To tell you the truth, I wasn't going to blog about it here; but since the topic came up already, I must tell you this is something I have been thinking about lately, but haven't had the opportunity to address just yet. Now, please keep in mind that what I'm going to say now is just my personal opinion, not something I claim to be the absolute truth.
I believe that the husband and wife should vote as one: meaning that, after discussing the possible options, both come to a mutual decision and the wife strengthens the husband's vote with hers. I think it's a shame if the wife disregards her husband's opinion and "cancels" his vote by choosing the opposite. And in my opinion, the same is true for adult unmarried daughters - they are under their father's authority until marriage.
Of course, in our generation things are often more complicated than that. Some women have no fathers (like myself); some have unbeliever fathers who are unwilling to step up as leaders of their families - and there are other examples of situations when the voting issue isn't very clear. For now, I do vote, trying prayerfully to give my support to the candidate who seems most God-honoring. However, I admit that I haven't thought enough about whether or not a woman should vote if she has no husband, father or brother to guide her.
I would love to hear thoughts from other ladies.