WATCH: Dissecting the Supreme Court's Top Marriage Arguments

There's no way to know exactly how the Supreme Court will rule -- or even when -- but considering how yesterday's oral argument went, it's okay to feel cautiously optimistic.

As expected, it looks like it will all come down to Justice Anthony Kennedy. Whichever side can persuade him to swing their way seems likely to emerge victorious in late June. Kennedy was tough to read during Tuesday's arguments, asking difficult questions of both sides; but he seemed to hone in on the issue of dignity.

When John Bursch, the attorney for the states defending marriage bans, tried to argue that it was inappropriate for LGBT couples to expect that marriage would bestow dignity on their relationships, Kennedy was quick to interrupt. "I don't understand this 'not dignity-bestowing,'" he said. "I thought that was the whole purpose of marriage. It bestows dignity on both man and woman in a traditional marriage. ... It's dignity-bestowing, and these [gay and lesbian] parties say they want to have that, that same ennoblement."

It's important to note that the concept of dignity played a major role in Kennedy's 2013 ruling in Windsor that overturned a key potion of the Defense of Marriage Act, as well as the 2003 Lawrence decision that overturned sodomy bans -- which Kennedy also authored.

But Kennedy also expressed concern that marriage has excluded same-sex couples for "millennia," and it seemed hasty for the court to take a stand at this point. It seems possible -- perhaps even likely -- that he remains undecided.

If that's the case, then the other justices may still manage to persuade him before a decision is made. Scalia raised questions about whether marriage equality would compel religious leaders to participate in ceremonies against their will -- a speculation that was easily shot down by his colleagues. Ginsberg and Sotomayor, on the other hand, repeatedly pressed Bursch on how marriage bans could possibly achieve the state's goals of encouraging responsible procreation.

"How does withholding marriage from one group... increase the value to the other group?" asked Sotomayor.

Bursch replied by stating that under rational basis review, the state did not have to answer that question.

With oral argument coming late in the court's term, most court-watchers expect a decision won't be handed down until the last day of the term at the end of June.