Getting married has little to do with the bible. Jewish people get married and they don't think that Jesus was the son of god. Muslim people get married and they read a different "bible". Athiests get married all the time. You don't need a priest to get married. You can go down to the local courthouse any weekday. Marriage is in principal simply a contract that unites two people in a business partnership that gives each spouse certain priviledges and responsibilties. If you don't believe this you have obviously never gone through a divorce.
Restricting a segment of the population, no matter how small, because of a unifying caracter trait is the definition of racism.
Besides, how will allowing gay marriage affect you? SERIOUSLY! It won't change your beliefs or impenge on your rights in any way.
Given the number of straight marriages that don't work out it might make more sense if all marriages were outlawed.
If you were wondering I am not gay. I simply see this as a situation of a restriction of freedom of choice, which to me is the most sacred freedom we have.