United States ambassador to Canada Paul Cellucci speaks to reporters outside the Canadian Conference of Defence Associations in Ottawa, in this March 3, 2005, file photo. Cellucci died after a five year battle with Lou Gehrig’s disease, June 8, 2013, according to media reports. (Chris Wattie/Reuters)

Paul Cellucci, a former governor of Massachusetts and U.S. ambassador to Canada, died June 8 at his home in Hudson, Mass. He was 65.

He had amyotrophic lateral sclerosis, or ALS, a degenerative and incurable neurological condition also known as Lou Gehrig’s disease. His death was announced by Michael F. Collins, chancellor of the University of Massachusetts Medical School, where Mr. Cellucci was involved in raising funds for ALS research.

Mr. Cellucci was considered a moderate cast in the mold of New England Republicans — fiscally conservative yet middle of the road on many social issues. In three decades in politics, first at the local level, he never lost an election.

He was elected lieutenant governor in 1990 and became acting governor in 1997 when his predecessor, William Weld, resigned to pursue an ambassadorship. Mr. Cellucci won election as governor in his own right in 1998.

His personality was more reserved than Weld’s, but he played a much larger role than a typical lieutenant governor and was credited with guiding Weld, a former federal prosecutor and political neophyte, through the political process during their 1990 campaign. Weld often called Mr. Cellucci his “co-governor.”

The two were credited with easing a state fiscal crisis and they easily won reelection in 1994.

After fending off a nasty primary challenge by state treasurer Joe Malone in the 1998 GOP primary, Mr. Cellucci defeated state attorney general Scott Harshbarger in the November election.

When Mr. Cellucci was nominated for the Canada ambassadorship by President George W. Bush in 2001, he resigned his governorship. His lieutenant governor, Jane Swift, was named acting governor and became Massachusetts’s first female chief executive.

Mr. Cellucci was a longtime friend of former President George H.W. Bush and was an early supporter of George W. Bush.

He was also a close friend of White House chief of staff Andrew Card, a former Massachusetts legislator.

Argeo Paul Cellucci was born April 24, 1948, in Hudson, Mass., where his father owned car dealerships. He graduated from Boston College and received a degree from Boston College Law School in 1973. He served in the Army Reserve.

His political career began in 1970, while he was still in law school, when he was elected to a local office in his home town. He served on the Hudson Board of Selectmen from 1971 to 1977 and in the state House of Representatives from 1976 to 1984. Cellucci was elected to the state Senate in 1984.

Survivors include his wife of 41 years, Janet Garnett Cellucci; two daughters; a sister; a brother; and four grandchildren.

— From news services and staff reports