Idaho voters approved a constitutional ban on gay marriage Tuesday, and rejected a proposition that would have limited the power of local governments to make land-use decisions.

With 25 percent of 952 precincts reporting, more than 66 percent of Idaho voters were in favor of the amendment, which not only bans gay marriage but also any domestic unions outside of traditional marriages.

Andrew Yoder, the campaign manager for Idaho Votes No, a group opposing the amendment, said he was not surprised by the results.

"It was always very clear that this was going to be a real uphill battle — in some sense, experts could have called the race six months ago," Yoder said. "But I believe there are a significant number of people in Idaho who have seen the way amendments such as this one create harm and are overreaching. This is the start of continuing work for a change that we believe in."

Bryan Fischer, the executive director for Idaho Values Alliance, which made the push to get the measure on the ballot, said the results were "good news for Idaho's families and children."

"I just think nationwide Americans recognize that marriage and the family represent the cornerstone of our civilization and we shouldn't be conducting mass social experiments," Fischer said.

Proposition 2, which pitted private property rights against the power of local governments to make land-use decisions, lost with more than 76 percent of voters casting no votes in early returns. With 221 out of 952 precincts reporting, only about 23 percent of voters were in favor of the proposal.

The race was closer on Proposition 1, which called on lawmakers to increase school spending by $219 million a year. Just over 56 percent of voters were against the plan, and nearly 44 percent were for it.

More than 59 percent of voters were in favor of a constitutional amendment designed to limit the use of money from the state's settlement with big tobacco companies to health-related purposes.