UPDATE | Supreme Court will take up gay marriage issue

WASHINGTON (AP) — Setting the stage for a potentially historic ruling, the Supreme Court announced today it will decide whether same-sex couples have a right to marry everywhere in America under the Constitution.

The justices will take up gay-rights cases that ask them to declare for the entire nation that people can marry the partners of their choice, regardless of gender. The cases will be argued in April, and a decision is expected by late June.

Proponents of same-sex marriage said they expect the court to settle the matter once and for all with a decision that invalidates state provisions that define marriage as between a man and a woman.

On the other side, advocates for traditional marriage want the court to let the political process play out, rather than have judges order states to allow same-sex couples to marry.

Same-sex couples can marry in 36 states and the District of Columbia.

That number is nearly double what it was just three months ago, when the justices initially declined to hear gay marriage appeals from five states seeking to preserve their bans on same-sex marriage. The effect of the court's action in October was to make final several pro-gay rights rulings in the lower courts.

Now there are just 14 states in which same-sex couples cannot wed, including Ohio. The court's decision to get involved is another marker of the rapid change that has redefined societal norms in the space of a generation.