The Senate voted 20 to 16 early today for final passage of a bill outlawing discrimination against people who are transgendered, ending a years-long fight in the General Assembly. Gov. Dannel P. Malloy has promised to sign the bill as soon as it reaches his desk.

As was the case in the House, every Republican voted against the bill, including five GOP senators who voted for a similar measure four years ago. Democrats Paul Doyle of Wethersfield and Joan Hartley of Waterbury joined all 14 Republicans in opposing the bill.

The bill is the first civil rights legislation to pass in Connecticut in recent decades without Republican votes. Passage of a gay rights bill 20 years ago and same-sex civil unions and marriage bills more recently all occurred with some support from the GOP.

Senate Minority Leader John P. McKinney, R-Fairfield, who voted for a similar bill in 2007, said he and some other Republicans were prepared to vote for a bill that outlawed discrimination on the basis of gender identity in housing, employment and most public accommodations. But they were uncomfortable that the protections reached into more private settings, notably bathrooms.

In a statement released after the vote, Malloy said, “This bill is another step forward in the fight for equal rights for all of Connecticut’s citizens, and it’s the right thing to do. It’s difficult enough for people who are grappling with the issue of their gender identity, and discrimination against them has no place in our society. Connecticut has lead the way in other civil rights issues and I’m proud to be able to support and sign this bill.”

During debate late Friday night, supporters offered at times emotional pleas to extend protection to people they said often struggle with their identity and suffer discrimination and mistreatment.

Opponents sought to amend the bill to make exceptions for gender distinctions in bathrooms and boardinghouses. They said their opposition to the bill was not an endorsement of discrimination, but an attempt to protect existing common-sense distinctions in bathrooms.

Sen. Beth Bye, D-West Hartford, became emotional as she described the evolution of public acceptance. Bye, who is gay, said she had once had to choose between her job and her sexual orientation.

There were times when teachers would lose their jobs for getting divorced, and when parents didn’t want their children in the classroom of a gay teacher, she said.

“But today, that doesn’t happen because we’ve built understanding,” Bye said.

Laws providing workplace protections always come first, she said. When it became illegal to fire someone for being gay, people began bringing pictures of their partners to work and talking about their personal lives.

“That’s always the first place to understanding,” Bye said.

Sen. Edward Meyer, D-Guilford, spoke of his boyhood friend and fellow tennis player Richard Raskind. As an adult, Raskind told Meyer, “Ed, I’m a woman in man’s body.”

Raskind later had surgery and became a woman, Renee Richards. Meyer said the change was “totally genuine,” and that his friend doesn’t just look like a woman and act like one; she thinks like a woman. “She is a woman,” he said.

“To send Renee Richards into a men’s bathroom, that would be very dangerous, because Renee is a woman,” he said. “To send Renee to male sleeping arrangements would be very dangerous, very inappropriate, because Renee Richards is a woman.”

Others sought to narrow the scope of the bill, which prohibits discrimination on the basis of gender identity or expression in employment, public accommodations, housing, public schools and other areas.

One was Sen. John A. Kissel, R-Enfield, who voted for a similar bill in 2007.

He spoke of the evolution of his views on the subject, and said the protection of transgendered people under the bill could bump up against longstanding distinctions made in bathrooms and locker rooms. Many constituents had asked him to preserve those distinctions, he said.

Sen. Len Suzio, R-Meriden, asked that opponents not be considered “narrow-minded bigots.” Seeking to exempt bathrooms, he said, would provide protection for women who could feel threatened by men entering their bathrooms, children, and transgendered people themselves, who could be mistreated.

“We’re all concerned, rationally, I think, about safety issues for the sexually vulnerable,” he said.

Sen. Jason Welch, R-Bristol, introduced an amendment that would carve out bathrooms, locker rooms and rental sleeping accommodations–like YMCAs–from the bill. Kissel introduced an amendment that would allow school boards to reassign an elementary school teacher for the rest of a school year if he or she changes gender identity or expression.

Both failed.

So did an amendment by Sen. Andrew Roraback, R-Goshen, that would have prohibited discrimination in housing, employment and other areas, but not in bathrooms, locker rooms and boarding houses. Roraback also voted for the 2007 bill.

“This amendment states affirmatively what I believe the public policy of the state of Connecticut ought to be, which is simply not to permit discrimination in any area with the one exception of that where we permit discrimination today, as between men and women in the use of private bathrooms, locker rooms and boarding houses and the like,” Roraback said.

But Senate Majority Leader Martin M. Looney, D-New Haven, said characterizing the legislation as a “bathroom bill” trivializes what it is really meant to do.

“It’s really about civil rights,” he said. “It’s really about discrimination. It’s really about inclusiveness in our society.”