Raising the curtain in what is destined to be a bitter, prolonged political battle, Republican legislators announced Tuesday that they willl introduce bills that would place a constitutional amendment on the 2012 ballot that would define marriage in Minnesota as only between a man and a woman.

Although state law already defines marriage in precisely those terms, a constituional amendment is needed to ward off court rulings that could overturn that law.

And having such a long period between now and next year's election, it will allow for "a statewide community discussion," said Sen. Warren Limmer, R-Maple Grove, one of the sponsors.

"It's time to bring it to the people," said Rep. Steve Gottwalt, R-St. Cloud.

Similar bills have been repeatedly been introduced in recent legislative sessions, but DFL majorities have consistently blocked their passage. With Republicans in charge of both the House and Senate, passage this year seems likely.

The proposed amendment was immediately denounced by DFL legislators and Gov. Mark Dayton, whose hands would be tied if it's approved. Constitutional amendments don't require a governor's signature and cannot be vetoed.