Kenneth H. Dahlberg is awarded the Distinguished Service Cross by Vice President Humphrey on January 24, 1967. Washington Post investigative reporter Bob Woodward used this photo to track down Dahlberg at his Minneapolis home during the investigation of the Watergate scandal. (Wally McNamee/THE WASHINGTON POST)

Kenneth H. Dahlberg, 94, a highly decorated World War II ace and multimillionaire venture capitalist whose endorsement on a $25,000 cashier’s check donated to the 1972 Nixon reelection campaign made him a notable figure in the Watergate scandal, died Oct. 4 at his home in Deephaven, Minn.

He had pneumonia, said his biographer, Warren Mack.

Mr. Dahlberg rose from washing pots and pans in a hotel kitchen to become one the nation’s foremost industrialists. He amassed a tremendous fortune by inventing in the 1950s the Miracle Ear hearing aid, an all-in-the-ear device so light and small it was a “miracle.”

After selling his company to Bausch & Lomb in 1994 for more than $100 million, Mr. Dahlberg became a venture capitalist. One of his earliest investments included the Minnesota-based Buffalo Wild Wings restaurant chain, which now has more than 800 locations across the country.

Beyond his success in business, Mr. Dahlberg was best known for his brief role in the Watergate affair.

On June 17, 1972, five men wearing surgical gloves were arrested after breaking into the Democratic National Committee’s sixth-floor suite in the Watergate complex.

Upon their arrest, the police recovered about 53 $100 bills stuffed in the men’s pockets.

The FBI traced the cash back to a Miami bank account controlled by one of the burglars, Bernard L. Barker, a Cuban-born American and onetime CIA employee.

Two months before the Watergate break-in, a $25,000 check endorsed by Mr. Dahlberg was deposited into Barker’s account.

At the time, Mr. Dahlberg, a Minnesota native, was serving as the Midwest finance chairman for Nixon’s reelection campaign. He had given the check as a donation to Maurice Stans, Nixon’s fundraising chief.

Washington Post reporters Bob Woodward and Carl Bernstein used Mr. Dahlberg’s check to prove Nixon was involved with the break-in at the Watergate.

“It was the first real connective glue between Watergate, its funding and the Nixon campaign,” Woodward said Thursday in an interview. “It showed and reinforced the idea of track the money, follow the money.”

Mr. Dahlberg was cleared of any wrongdoing. Nixon won reelection in 1972, but the Watergate scandal plagued his second term. Woodward and Bernstein’s Pulitzer Prize-winning efforts eventually led to Nixon’s resignation in August 1974.

Kenneth Harry Dahlberg was born June 30, 1917, in St. Paul, where his father was a motorman on the city’s streetcars.

After high school Mr. Dahlberg got a pot-cleaning job at the Lowry Hotel in St. Paul before he was drafted in 1941.

As an Army Air Forces pilot in Europe, Mr. Dahlberg shot down 15 enemy planes — qualifying him as a rare triple ace — including one mission where he got four kills while flying over Paris.

Mr. Dahlberg was brought down three times himself. On the last occasion, in February 1945, his plane crashed near Metz, Germany, and he was captured by a Nazi patrol.

He attributed his business acumen to the months he spent as a prisoner of war in a stalag outside Munich.

“The first time I traded a cigarette to a German guard, I got a turnip.” Mr. Dahlberg once told an interviewer. “The second time . . . it cost me two cigarettes for a turnip. The third time, it took two cigarettes for a half a turnip. That was 100 percent a month inflation. Finally, the guard had no turnips at all. My currency was worthless.”

By May 1945, Mr. Dahlberg was released, and he headed back to Minnesota. His decorations included the Distinguished Service Cross, the military’s second highest honor for valor, two awards of the Distinguished Flying Cross and the Purple heart.

Through friends, Mr. Dahlberg got a job at Telex, a manufacturer of hearing aids and hospital communication equipment. In 1948, he and his brother founded a hearing-aid company and seven years later introduced the Miracle Ear.

During his military days, he became friends with future Republican politician Barry Goldwater, and Mr. Dahlberg served as deputy chair of fundraising for Goldwater’s 1964 presidential bid. Four years later, Mr. Dahlberg served as the Nixon campaign’s Minnesota finance chairman.

Survivors include his wife of 64 years, the former Betty Jayne Segerstrom, of Deephaven, Minn., and Carefree, Ariz.; three children, Nancy Dahlberg of Sarasota, Fla., Dede Disbrow of Edina, Minn., and K. Jeffrey Dahlberg of Colorado Springs; a brother; two sisters; seven grandchildren; and five great-grandchildren.

A few days after the Watergate break-in, Nixon discussed the incident with his chief of staff, H.R. Haldeman, in the Oval Office.

In the recorded session, Haldeman informed the president that the FBI had traced the money “to a name, but they haven’t gotten to the guy yet.”

“Would it be somebody here?” Nixon asked.

No, Haldeman said, it was a man named Ken Dahlberg.

Nixon replied: “Who the hell is Ken Dahlberg?