WASHINGTON —  Theodore B. Olson, the conservative attorney who helped win the right to gay marriage in California, died Wednesday at age 84.

Olson was a good-spirited and gracious advocate who won landmark conservative rulings from the Supreme Court.

They included the Bush vs. Gore decision that made George W. Bush the president, and the Citizens United ruling that struck down the bans on campaign spending.

Four years ago, he represented so-called Dreamers in a Supreme Court immigration case and won a 5-4 ruling that blocked the first Trump administration from repealing protection for the young immigrants who came to this country with their parents.

Olson surprised many when he agreed to lead the challenge to California’s Proposition 8 and its ban on same-sex marriages.

“I wanted to convey the message that this was not Republican or Democrat, conservative or liberal, that this is about human rights and human decency,” he said in an interview with The Times.

Olson sued on behalf of two gay couples, and Judge Vaughn Walker ruled that it was unconstitutional discrimination to deny them the right to marry.

The proponents of the proposition appealed, but the Supreme Court ruled in 2013 that they did not represent the state and had no standing.

While the decision was procedural, it cleared the way for same-sex couples to marry in California. Two years later, the court ruled that the Constitution protected gay marriages nationwide.

He said he lost some conservative friends at the time who were no longer willing to join him for lunch or come to his house for dinner.

The case “changed my life a lot. When I talk about it, I get very emotional,” Olson said.

Just last week, California voters formally removed Proposition 8 from the state Constitution and enshrined the right to marry.

Olson was born in Chicago in 1940 and grew up in Mountain View, Calif.

He was a law student at UC Berkeley in 1964, where he said he was one of the only students who supported Republican Barry Goldwater in his losing race for the presidency.

In 1980, Olson was an attorney at Gibson Dunn in Los Angeles when Ronald Reagan was elected president.

Reagan chose William French Smith, a Gibson Dunn partner, as U.S. attorney general. Smith then chose Olson to head the Justice Department’s Office of Legal Counsel.

Olson would later represent Reagan as his personal attorney after he left the White House.

In 1984, he left the administration and helped set up Gibson Dunn office in Washington.

For next 40 years, he worked there, except for a four-year stint as U.S. solicitor general representing the Bush administration.
He argued 60 cases before the Supreme Court as both a private advocate and government attorney.

“Ted has been the heart and soul of Gibson Dunn for six decades and made us who we are today,” said Theodore J. Boutrous Jr., partner at Gibson Dunn in Los Angeles who regularly collaborated with Olson on major cases. “He was not just an incomparable lawyer, mentor, role model, and friend, but he has made immeasurable contributions to the rule of law, our Constitution, and our country. We will miss him with all our hearts.”

The Bush vs. Gore case played out in five days in early December 2000. Olson filed an emergency appeal seeking to halt the recount of untabulated paper ballots in Florida. He said that because there were no agreed-upon standards for deciding when a defective ballot could be counted, the result would differ county by county.

At midday on a Saturday, the court granted his appeal by a 5-4 vote and agreed to hold a hearing on Monday. Late that Tuesday evening, the court ended the Florida recount in an unsigned opinion with four dissents.

Upon taking office, Bush chose Olson to represent his administration before the court.

Olson was in his Justice Department office early on Sept. 11, 2001, when he got a call from his wife, Barbara. She had boarded an American Airlines flight to Los Angeles that was hijacked. A few minutes later, the call cut off. The plane had crashed into the Pentagon, killing all aboard.

He said he believed he was fortunate to have a busy legal career as well as many friends to get through the grief.

He later remarried, and his wife, Lady Booth Olson, was a Democrat and more liberal. She said the gay marriage case had changed him.

“When you look at discrimination in the face — these people who got up and testified for hours about what it’s like to be denied the right to marry, it’s transformative,” she said in a 2013 interview with The Times. “I think he’s starting to open his mind and hear a little bit more than he used to.”