Ralphie May, a loud and large comedian known for his extensive touring and comedy specials on Netflix and other outlets, died on Friday in Las Vegas, where he had been in residence at Harrah’s casino. He was 45.

His publicist, Stacey Pokluda, said the cause was cardiac arrest. She said he had been treated for pneumonia and had canceled some shows over the past month.

Mr. May, born Ralph Duren May on Feb. 17, 1972, in Chattanooga, Tenn., was a 17-year-old student in Arkansas when he won a contest to open for Sam Kinison, who became a mentor of sorts. (Mr. Kinison also died young, at 38, in a car accident in 1992.) The experience led Mr. May to move to Houston to try comedy full time.

He worked the stand-up circuit for years, and in 2002 made his feature film debut in the comedy “For da Love of Money,” drawing an approving notice from Dave Kehr in his review in The New York Times.