Robert Goulet, the man Ed Sullivan called the "American baritone from Canada," has died at a Los Angeles hospital.

A spokesperson for the iconic singer says he passed away on Tuesday while waiting for a lung transplant. Last month, Goulet was diagnosed with a rare form of pulmonary fibrosis, a lung disease.

Despite his illness, his wife of 25 years says he didn't lose his sense of humor, even as he waited for the transplant.

When doctors were about to insert a breathing tube, Vera Goulet said he told them to "'Just watch my vocal cords,'" reports the Associated Press.

Goulet was born in Massachusetts to French-Canadian parents. But he spent much of his youth in Canada, and hosted a popular variety show called "General Electric's Showtime."

According to his official website, Goulet performed for the Edmonton Symphony Orchestra at the age of 16. Later, he was awarded a singing scholarship to the Royal Conservatory of Music at the University of Toronto. Goulet firmed up his musical theatre career for a season with Vancouver's Theatre Under the Stars in 1957.

In 1960, he won the Theatre World Award for his debut Broadway performance as Sir Lancelot in Camelot, which also starred Richard Burton and Julie Andrews. The production originally previewed at Toronto's O'Keefe Centre.

One of his most avid supporters was Ed Sullivan, the 1950s and 1960s variety show host who catapulted hundreds of entertainers into superstardom. He appeared on the Ed Sullivan show 17 times.

Goulet was awarded a star on the Hollywood Walk of Fame in 1975 and received a Canadian Walk of Fame star in 2006.

He recorded 60 albums during his career and was a Grammy Award winner, and also appeared in dozens of television shows and movies. In the 1960s, he starred in his own television show called "Blue Light."

In recent years, Goulet has gained new audiences by starring in humorous, often self-deprecating commercials and TV spots. He has appeared in or lent his voice to episodes of "The Simpsons," "The King of Queens," and the "Howard Stern Show."

Goulet was also a spokesperson for the American Cancer Society. He was diagnosed with prostate cancer in 1993 and publicized the need for early detection.

Goulet is survived by his wife, three children, and two grandchildren. Robert Gerard Goulet was 73.