David Boies, the high-profile attorney who helped win enactment of same-sex marriage rights in California, said advocates are forming their strategy to extend the right to all 50 states.

“Our goal is to have marriage equality, that is guaranteed by the United States constitution, enforced in every single state in the Union,” he said Sunday on CNN.

Roughly three-dozen states currently prevent same-sex marriage. Boies did not discuss specific targets but said there's not any state that advocates are giving up on.

Boies was one of the lawyers who challenged Proposition 8, the narrowly approved California voter referendum that banned same-sex marriage there.

The Supreme Court, on procedural grounds, last week declined to rule on the merits of Proposition 8, which left in place a trial court’s decision invalidating it.

The decision, alongside a ruling that largely struck down the federal Defense of Marriage Act, was a big victory for same-sex marriage advocates. But the rulings did go as far as advocates wanted, failing to provide a nationwide right to same-sex marriage.

Boies said pro-gay marriage groups – the American Foundation for Equal Rights and the Human Rights Campaign – are determining how to move forward to win the right to marry in all states.

He predicted it would be a combination of state legislation, lawsuits and ballot measures.