MONTPELIER, Vt. — F. Ray Keyser Jr., a three-term lawmaker and former speaker of the Vermont House, took office as governor following the 1960 elections as cracks were beginning to appear in generations of dominance of state politics by a handful of Republican families.

It was two years later that Keyser was defeated by Phil Hoff, the Democrat who broke more than a century’s hold on the Vermont governor’s office by the Republican Party, marking the start of state’s shift from one of the most conservative in the country to one of the most liberal.

“He was a boy wonder,” former Republican Gov. Jim Douglas said of Keyser, who was elected at age 34, making him Vermont’s youngest governor.

Keyser died Saturday at age 87 at his daughter’s home in Brandon, said Dennis Cilley, director of the Boardway & Cilley Funeral Home. Cilley said Sunday that he didn’t know Keyser’s cause of death.

Keyser’s 1962 defeat was the last time an incumbent Vermont governor was ousted in the general election. It ended 109 years of Republican control of the Vermont governor’s office.

Douglas said Keyser also enjoyed the distinction of being the first Vermont governor still living 50 years after his election. Hoff, Keyser’s successor, was the second.

“Vermont has lost a faithful public servant who showed his love for this state and its people through his years of service,” Democratic Gov. Peter Shumlin said Sunday in a statement. “I know I join all Vermonters in being thankful for Gov. Keyser’s dedication to Vermont.”

Keyser was born in Chelsea on Aug. 17, 1927. His father, F. Ray Keyser, served in the Legislature in the 1930s before becoming a Supreme Court justice. The elder Keyser heard cases until he was 90 and died in 2001 at 102.

The younger Keyser served in the U.S. Navy during World War II. He was a graduate of Tufts University and the Boston University School of Law.

During his two years leading Vermont, Keyser initiated a statewide planning program and established the Vermont Industrial Building Authority. Also during his administration, Vermont made extensive investment in its park system, and the state budget was balanced without assessing new taxes.

But Keyser’s time as governor was unpopular.

Hoff eked out a narrow victory in the 1962 election with the help of The Vermont Independent Party, a group of anti-Keyser Republicans.

After leaving office, Keyser served on the boards of several corporations, including a time as chairman of the Central Vermont Public Service Corp. until its merger with Green Mountain Power, Vermont’s largest electric utility.

He also is a past president of the Vermont Golf Association. Shumlin ordered that flags around the state be flown at half-staff in Keyser’s honor. The flag tribute begins at sunrise Monday and will continue until sunset on March 16.

A memorial service is planned for the spring in Chelsea, Cilley said.