MADISON, Wis. — The state Senate is set to finalize Wisconsin’s call for a convention of states to add a balanced budget amendment to the U.S. Constitution.

Republicans say the amendment is needed to rein in federal spending. It takes 34 states to trigger a convention. Wisconsin would be the 28th. Opponents fear the convention could spiral out of control leading to all manner of ill-conceived amendments.

The Senate is scheduled to vote Tuesday on resolutions calling for a convention and promising Wisconsin’s delegation will work only for a balanced budget amendment. Also on the agenda is a bill that lays out the delegate appointment process.

All three proposals passed the Assembly in June. Senate approval would finalize the state’s call. Gov. Scott Walker’s signature isn’t necessary for the resolutions.