WASHINGTON - Same-same marriage is going before the U.S. Supreme Court in two cases this week.

Justices will hear arguments on California's Proposition 8 Tuesday and will take up the federal Defense of Marriage Act on Wednesday. Supporters say the public should decide, while opponents argue that voter-approved marriage bans are unconstitutional.

The cases represent a battle over a traditional concept of marriage and the rights of families in same-sex relationships. One of the major issues facing the court is whether it can or should make a ruling to broaden the legal definition of marriage.

The arguments come at a time when support for same-sex marriage is gaining traction. GOP strategist Karl Rove says he can imagine a Republican candidate in the next presidential campaign supporting gay marriage, Republican Sen. Rob Portman (R-Ohio) announced earlier this month that he now believes in the freedom to marry after finding out that one of his sons is gay.