Colorado voters overwhelmingly outlawed gay marriage Tuesday, joining more than two dozen other states in amending their constitutions to declare marriage must be a union between a man and a woman.

A second proposal that would award same-sex couples some of the same benefits enjoyed by married spouses under state law was failing.

Jon Paul, director of the pro-ban group Coloradans for Marriage, said he knew it would be a tight race in part because of the money poured into the race by Colorado-based software millionaire Tim Gill, a deep-pocketed supporter of gay rights.

Check Your State, Check Your Race by clicking BALANCE OF POWER dropdown menu above.

• Click here to visit YOU DECIDE 2006, FOXNews.com's complete election center.

"We knew we were in for a fight from the beginning. But we also knew that Coloradans believed marriage was between one man and won woman. We just had to make sure that people got to vote for it," Paul said.

With 61 percent of the projected vote counted, the gay marriage ban Amendment 43 had 57 percent support to 43 percent against it, or 608,466 votes to 460,349. Referendum I, the domestic partnerships proposal, was losing 55 percent to 45 percent, or 584,524 votes to 484,268.

Facing the second-longest ballot in Colorado history, voters also overwhelmingly rejected a proposal to legalize adult possession of up to an ounce of marijuana, a proposal which Denver voters approved last year. Amendment 44 lost with 61 percent voting against it.

They also approved a ban on all gifts over $50 to any lawmaker or government employee. Experts at the National Conference of State Legislatures said Amendment 41 gives Colorado one of the toughest government ethics laws in the nation.

Voters also rejected Amendment 40, which would have limited judges on the Colorado Court of Appeals and the Colorado Supreme Court to three, four-year terms.

The other high-profile issues on the 14-item state ballot included Amendment 42, which would raise Colorado's minimum wage from $5.15 to $6.85 per hour, adjusted annually for inflation. That ballot measure was too close to call late Tuesday.

Colorado was one of eight states where voters were deciding whether to amend their state constitutions to ban gay marriage. Twenty states have already done so and six more joined them Tuesday.

The dominant issue for many was gay marriage.

Business owner John Lindsey, 48, of Glenwood Springs voted for Amendment 43 and against Referendum I.

"I'm not anti-gay, so to speak, but there are a lot of ramifications that go around that," said Lindsey, a married Republican who described himself as a traditionalist.

Among other things, Referendum I would allow the couples to adopt children and require alimony and child support if they separate. It would also ensure that their partners can make medical decisions for them and the right to inherit property even without a will.

Referendum I says domestic partnerships are not marriages, though opponents said it delivered the same benefits enjoyed by spouses.

Supporters of Amendment 43 hoped a recent court decision in New Jersey ordering lawmakers to endorse gay marriage or civil unions would boost turnout here. Yet Colorado was rocked last week by the resignation of evangelical leader Ted Haggard — a prominent backer of the amendment — amid allegations that he paid for gay sex.

Denver pollster Floyd Ciruli said the allegations against Haggard likely helped sway undecided voters against Referendum I.

"The goal of the gay-rights advocates was to keep it very low key," Ciruli said, but instead Haggard's troubles put a spotlight on the issue.

"What they had was a huge controversy on the front page related to the most controversial aspects of the gay lifestyle," Ciruli said.

State law already defines marriage as being between one man and one woman, but Amendment 43 supporters said that could be overturned by a judge and the better move was a constitutional amendment.

Joshua Tafoya, 22, a literature major at Mesa State College in Grand Junction, voted against the marriage amendment and yes on Referendum I. He said whatever goes on in someone's bedroom isn't his business or the government's.

"Personally if it were me, and I was on my deathbed, I would want to give what I want to who I want without the state intervening," said Tafoya, a single Democrat.

Gill contributed some $3 million in backing Referendum I and fighting Amendment 43. On the other side was Focus on the Family, the Colorado Springs-based evangelical Christian organization and its public policy arm contributed at least $874,000.

Carrie Gordon Earll, director of issues analysis for Focus on the Family's public policy arm, said most voters had made up their minds before the Haggard scandal broke last week.

She said Colorado voters saw Referendum I as marriage by another name.

"Referendum I was sold to the public as hospital visits, and clearly it was much more than that. It was the legal equivalent of marriage," she said.