Professional gambler raking in the cash on US game show Jeopardy!

A professional gambler with nerves of steel and an encyclopedic mind has just surpassed the US$1 million (S$1.4 million) mark in earnings on the popular US television quiz show "Jeopardy!" -- in lightning quick fashion.

James Holzhauer, 34, is only the second contestant in the show's decades-long history to pass that mark in regular season play, after the legendary Ken Jennings. Well, legendary for the show's avid fans.

While it took Jennings, a computer scientist from Utah, 74 episodes to amass his fortune, Holzhauer has earned US$1.06 million in just 14 appearances.

The gambler with the wide grin is now aiming to best the US$2.52 million in prize money set by Jennings during his long string of victories in 2004.

"This is absolutely insane," Jennings said on Twitter of the success of Holzhauer, who has repeatedly broken his own record for the most money won on a single night -- it currently stands at US$131,127.

ESPN is covering Holzhauer's episodes on its Chalk betting section. Rock bands are tweeting at him when he answers questions about them.

"Dream job: pro sports bettor and Jeopardy contestant," Holzhauer tweeted.

HOW DOES HE DO IT? 

"Jeopardy!" is one of the oldest television quiz shows in the United States, dating back initially to 1964, and to 1984 in its current format with host Alex Trebek.

It is a testament to the show's beloved nature that when Trebek recently announced he was battling cancer, the news trended on Twitter.

Every night, three contestants are presented with trivia questions in various categories and asked to come up with the answer -- in the form of a question.

A recent example: "Rulers of this Empire included Darius I and his son Xerxes I."

Holzhauer's correct answer: "What is Persia?"

A monetary value is attached to each question, and the first contestant to press a buzzer gets to answer.

Holzhauer has proved to be super fast on the buzzer.

But more importantly, in racking up the wins, he has also employed a novel -- but risky -- strategy befitting his day job in Vegas.

He frequently zeroes in on the high-value questions first to quickly amass money, and then unhesitatingly bets big -- really big -- on his ability to offer the correct answer when he lands on a special Daily Double question.

Explaining his success to ESPN, Holzhauer said: "There's not a lot of professional gamblers out there.

"Even if people wanted to be, I don't think a lot have the mindset that 'Oh, I can just put in US$10,000 and if I lose, OK, I move on with my game and keep playing the rest of the game with a level head."

Holzhauer's remarkable run has earned him legions of admirers -- including Jennings, the man whose record he is threatening to break.

"I've always wanted to see someone try Jeopardy! wagering this way who had the skills to back it up," Jennings said.

"I don't feel I get enough credit for making small, sensible Jeopardy wagers, which helped the show with its prize budget," he quipped in another tweet.