The issue is not who wins or loses. The issue is whether we preserve the rule of law or not. When the Supreme Court struck down the Defense of Marriage Act, there were not many complaints from conservatives. They didn't like the outcome, but they loved the reasoning. The Court said marriage was a state, and not a federal, issue.
The problem with liberals is that they don't care how they win. If they have the Supreme Revolutionary Council, formerly known as the Supreme Court, rule that the Equal Protection Clause of the 14th Amendment mandates Gay Marriage, they're fine with that. Conservatives, like me, see that as a serious problem, not because of the outcome, but because of how it was reached. The 14th Amendment was drafted and ratified by Republicans in 1868, when homosexual acts were illegal in every state. It was intended to keep state courts in the former Confederacy from mistreating free blacks, especially freed slaves. The only bearing it had on marriage was mixed race marriages were made legal. It did not mention same sex marriage. It would never have been ratified if it did mention same sex marriage. The consent of the governed was given only to the 14th Amendment's meaning at the time it was passed. Reinterpreting it with a new meaning now is tyranny. Changing the Constitution was supposed to require an Article V ratification process. It was not supposed to be some far-fetched argument in a court case that even the judges writing the opinion don't really believe was the intent of the Constitutional wording or Amendment in question.
It was also unnecessary to get the same sex marriage outcome. Under the full faith and credit clause, it could easily have been held that a legal marriage performed in one state had to be recognized by all states. This would have left marriage a state decision.