Topeka ? Senators were quick to adopt a proposed amendment to the Kansas Constitution banning same-sex marriage, but the House may not move as fast.

The proposed amendment also would prohibit civil unions for gays and lesbians and would declare that only couples in a union of one man and one woman would be entitled to benefits normally associated with marriage.

The Senate’s vote Thursday was 28-11, giving supporters one vote more than the two-thirds majority necessary for adoption in the 40-member chamber. The measure went to the House, with some supporters hoping for a statewide vote April 5.

But key House Republican leaders were not sure how quickly their chamber would act on the proposed amendment, which mirrors one the Senate approved but the House rejected last year. Adoption of the amendment in the House requires 84 of 125 votes.

“I’m going to count noses and see how many votes there are and then we’ll decide what we’re going to do,” said House Speaker Doug Mays, R-Topeka, who supports the measure. “I’m not going to run a marriage amendment only to have it fail like last year.”

The House must adopt the measure by Feb. 11 for it to appear on the ballot in April, when Kansas holds city and school board elections. Voters’ approval by a simple majority would add the amendment to the state constitution.

Backers of the amendment said it would protect the traditional definition of marriage — defined in state statute since 1867 — from legal challenges. They also said such unions form strong families and are vital to society.

“Can we be sure that no activist judges or officials exist in Kansas?” said Sen. Dennis Wilson, R-Overland Park, who voted for the measure. “An amendment to our constitution is the only way to protect the sacred institution.”

Gov. Kathleen Sebelius and some legislators have said an amendment isn’t necessary to protect marriage, given existing Kansas law. Other critics consider the measure discriminatory.

“Never before in the history of our state have we added an amendment to the constitution that proactively discriminates against people,” said Sen. John Vratil, R-Leawood, an opponent of the measure. “The people we’re discriminating against are not a threat to my marriage or your marriage. They’re not a threat to our children.”

The Senate’s vote came on the fourth day of the legislative session, without having public hearings or a committee review. Debate lasted less than an hour.

Senate GOP leaders questioned the need for hearings or committee review, noting last year’s debate. But opponents of the amendment said the Senate’s quick action hurt efforts to present their arguments.

Last year, voters in 13 other states, including Missouri, amended their constitutions to ban gay marriage.

Some supporters of a Kansas amendment cited the votes in other states as a reason for acting quickly, arguing that Kansas voters would have overwhelmingly approved an amendment had they been given the opportunity.

“It goes to the very core of who we are as a civilization,” said Pat Bullock, director of missions for the Heart of Kansas Southern Baptist Association. “When you change the definition of marriage, you change the definition of morality.”

Richard Donner, executive of the Kansas Unity and Pride Alliance, a gay rights group, called the amendment “mean-spirited.”

“It should not even be considered as part of the constitution — or the constitution of any state,” he said. “It’s a civil rights issue.”

Senators voted 28-11 against a proposal to narrow their measure so that it mirrored the existing Kansas law. Such a change would have made it possible for the state to allow civil unions or grant other benefits to unmarried couples.

Freshman Sen. Vicki Schmidt, R-Topeka, said she offered the proposal to narrow the measure because she wanted to give Kansans a chance to vote on existing policy on marriage.

Other senators said her proposed change would allow civil unions that would be same-sex marriage in all but name.

In other action:

• Legislators and other officials participated in a Statehouse ceremony honoring Dr. Martin Luther King Jr. The 76th anniversary of King’s birth is Saturday.
• Attorneys on both sides of a school finance lawsuit talked to senators about a Kansas Supreme Court ruling mandating improvements in education funding by April 12.