I do not live in California. But I live in Massachusetts; it is where I was born and raised. And I am proud of the position of my state regarding homosexual marriage.
Mormons for Marriage is a website, written by a group of members of the LDS church outlining ways in which supporting marriage for all couples - homosexual or heterosexual - can still be in harmony with the LDS church's teachings. If you haven't gotten a chance to see it already, I would suggest browsing around to see what these thoughtful people have to say.
There are many different reasons I choose to support my homosexual brothers and sisters in this this way, but I would say that the main one is that I see no compelling argument as to why these rights/privileges (i.e. to see their sweetheart one in the hospital; to adopt a child together, with their loved one; to call their union "marriage" when that is effectively what it is) should NOT be extended to heterosexual unions. I could go through the LDS newsroom article point by point and outline the ways that I disagree, the ways that I think it uses biased sources, and so forth, but I do not really want to get into that. If anyone is really interested, I will. I would much rather focus on the good that all people share, the ways that we stand on common ground, instead of the things that we find distasteful in one another.
I truly love about this religion in terms of principles, doctrine, and culture. Similarly, there is much I struggle with, including the formal position by the church's leaders on this issue (it would actually probably be fair to say I struggle with a majority of the teachings, and it would be dishonest to claim otherwise). However, I cling to core principles of Christlike love, the value of each individual soul, and the idea that we are continually progressing, moving from grace to grace.
I love the idea of divine potential within each of us. I love the countless opportunities to share experiences, to serve one another, and to receive love from others in the form of service.
It is with those ideals in mind that I support gay marriage.
I will obviously not be telling anyone how to vote. But for friends and strangers in California faced with this ballot initiative in a few weeks, I would urge you to charitably look inside yourself, consider different perspectives, and TRULY examine this question before you cast your vote.