Mel Evans/Associated Press

I.B.M.’s Watson may have pummeled Jeopardy! champions Ken Jennings and Brad Rutter last month, but last week, a New Jersey Congressman beat the question-and-answer supercomputer.

To be sure, it was no ordinary politician. Representative Rush D. Holt Jr., a New Jersey Democrat, is a physicist who spent the nine years before he won his first congressional race in 1998 as the assistant director of the plasma physics laboratory at Princeton University.

Back in the 1970s, Mr. Holt recalled in an interview last Thursday, he tried his hand at Jeopardy!, and came away a five-time winner. He said he participated in the event in Washington, organized by I.B.M., to underscore the importance of government research funding and science education — and for the sheer cerebral sport of taking on Watson.

I.B.M.’s previous celebrity supercomputer, Deep Blue, beat the world chess champion Gary Kasparov. “But engaging in word play, which is so much a part of Jeopardy!, is very different than playing chess,” Mr. Holt observed.

Mr. Holt finished his round with 8,600 points to Watson’s 6,200. How did he do it?

By parsing the double-meaning of words more nimbly than Watson and betting big on a Daily Double and winning, Mr. Holt said.

The representative, for example, did well in the category Presidential Rhymes.

Clue: “Herbert’s Military Operations.”

Answer: “What are Hoover’s Maneuvers?”

In the category Fashion, Watson proved a wizard on haute couture and hemlines. “The Silicon kid beat me badly on that one,” Mr. Holt said. (Here’s more on how computers can be so smart at times, yet so dumb at others.)

But Mr. Holt really gained the upper hand when he hit a Daily Double, allowing a contestant to bet as much money as he or she has. Mr. Holt bet $3,000.

The category: “Animals I Fear.”

The clue: “Hippophobia”

“Somehow,” Mr. Holt said, “I recalled that hippopotamus means ‘river horse’ in ancient Greek.”

He correctly answered, “What is Fear of Horses?”

The representative came away a winner, but also suitably impressed by Watson. It was only one round, not a complete game. And Watson has not always won in the past. It won 71 percent of its warm-up matches with human Jeopardy! champions in the months before its televised match against Mr. Jennings and Mr. Rutter.

Still, Mr. Holt scored a minor triumph for the often-castigated political class. “I think more of Congress just hearing about it,” said Tom M. Mitchell, a computer scientist at Carnegie Mellon University and an artificial intelligence expert.