In what activists are calling a historic development, the Maryland Senate Thursday evening voted 25-21 to pass the Civil Marriage Protection Act, a bill that would allow same-sex couples in the state to wed.

The bill now goes to the House of Delegates, where most political observers say it will pass within the next two weeks. Gov. Martin O’Malley has said he will sign the bill if it gets to him.

The vote to give final approval of the bill came shortly after the Senate voted 30-17 to limit debate to 30 additional minutes each for supporters and opponents.

In a development that surprised some observers, senators didn’t use all of that time, prompting Senate President Thomas V. Mike Miller (D-Calvert and Prince George’s Counties) to order a roll call vote on the bill.

The vote was identical to a preliminary vote on the bill held the previous day in terms of those voting for and against it except that one senator who voted no in the preliminary vote — Joanne Benson (D-Prince George’s County) — was absent for the final vote.

“I’ve never been prouder to be a Maryland State senator than I am tonight,” said Sen. Jamie Raskin (D-Montgomery County), a sponsor of the bill and the designated floor leader for the bill’s backers.

“I just want to say that for me, the issue is summarized by this thought: It is a fundamental wrong to deny our citizens a fundamental right,” he said.

Raskin and Sen. Nancy Jacobs (R-Cecil and Harford Counties), the Senate’s minority leader, each praised their fellow senators on both sides of the issue for keeping the debate civil and dignified.

But Jacobs, who acknowledged she expects the House of Delegates to follow suit and pass the bill shortly, told her colleague in a floor speech that the issue won’t end with the legislature’s approval of the measure the governor’s signature.

Pointing to one of her colleagues who raised the issue of a voter referendum in Maryland on same-sex marriage, Jacobs said, “Well, when we knew we did not have the votes, that’s what we started investing our time in.”

“We’ve met with people all around the country who have run successful referendums on this issue,” she said. “And I just guarantee the people in the State of Maryland who feel very strongly about this issue that you will see it again and you will see it at the ballot box.”

Discussion of the bill in the House of Delegates is set to begin Friday with a hearing of the House Judiciary Committee that lawmakers say is likely to be far more rancorous than the relatively gentile debate tonight and Wednesday in the Senate.

Earlier in the day on Thursday, State Sen. Richard Madaleno (D-Montgomery County), who is gay, urged his colleagues to afford him and his partner, along with thousands of same-sex couples in the state, the right to marry during the second day of debate on a same-sex marriage bill.

Madaleno was one of about a dozen senators who spoke today for or against the  measure. Observers expect it will win approval by the full legislature this spring.

Madaleno noted that the bill “reiterates that no religious denomination will ever be required to recognize or perform or bless or celebrate any marriage that is against its belief.”

At the same time the measure would provide “full equality under the law for thousands of same-gender couples in our state, couples like Mark and myself” through civil marriage, he said.

“Many of you know Mark … my partner. But even using that term partner sounds a little odd,” he said, noting that the two had a church wedding ten years ago with friends and family members attending.

“He in my heart is my spouse, even though the laws in the State of Maryland do not say he is,” Madaleno said during a Senate floor speech.

“But to the law, he remains a legal stranger to me. He is my partner. I wouldn’t ask any of you to call your spouse your partner because that makes it sound as if he’s your business associate, that your spouse is your business associate and not the person you choose to spend your life with.”

Opponents of the bill, including Sen. Brian Simonaire (R-Anne Arundel County), argued that the bill would “redefine” marriage and damage it as an institution that serves as the foundation of all societies.

“Unintended consequences — that is the subplot of today’s vote,” Simonaire said. “Yes, this bill affects homosexual individuals wanting to marry. But as we’ve seen in other states, it also affects young, impressionable students in our school system who are taught the homosexual world view.”

“It may also affect teachers and public employees who lose their jobs due to their religious beliefs if they are unwilling to teach the promotion of same-sex marriage,” he said.

Backers of the bill, including Raskin, the floor leader on behalf of the measure, disputed that assertion, saying the state education authority and local boards of education throughout the state decide the content of school curricula, with input from local communities.

Sen. Allan Kittleman (R-Howard County), the only Republican supporting the bill in the Senate, said he struggled over the issue of same-sex marriage but came to realized that it is a matter of civil rights and equal justice for all Maryland residents.

“It is the right thing to do,” he said. “The time has come. Today is that time.”

The Senate voted on Wednesday 25-22 to give preliminary approval of the bill by passing a committee report recommending that the bill be enacted into law. Most observers of the legislature saw that vote as confirmation that senators would approve the bill in a final vote on Thursday or possibly early Friday.