Sorry, but this is one of those issues where it's all going to be one way or another. The huge majority of states would never approve gay "marriage", but eventually the gay lobby will manage to establish it in a few states. Liberal state supreme courts will impose it, as in Massachusetts, or a goofball state governor like the one in Illinois will simply start issuing marriage licenses to gays without authorization, and his goofball attorney general will back him up.
Once that happens in a few states, including possibly a big state like California or New York, that's when the demand will start to rise to make gay "marriage" the "law of the land". The morning shows and women's magazines will be filled with sob stories about loving gay "couples" who are trapped in their home state. We'll hear about John, who received a lucrative job offer in Kansas, but couldn't move there to accept it because his "marriage" to Jim would become void. We'll hear about Sue, who wants to attend a college in Minnesota where there's an excellent sociology program, but she can't move there with her "wife" Janet without their "marriage" becoming void.
This will be called "The New Apartheid". We'll hear about all the bureaucratic difficulties created by this. Federal agencies have to keep two separate sets of records, one for "gay" states, one for non-"gay" states, at a cost of millions.
Then we'll have liberal cities and counties within conservative states offering "sanctuary" to gay "couples" by promising to recognize their "marriage", in violation of state law (just as some are now doing by offering sanctuary to illegal aliens).
A system like that simply won't survive. There are really only two choices. If we don't amend the Constitution to limit marriage to one man and one woman, the Supreme Court will impose nationwide gay "marriage" on us, using the 14th Amendment, followed by additional court orders for nationwide gay adoption, gay school curricula, gay affirmative action, and so on.