Vacation’s almost over and it’s time to get your head back into the game.

Not the office game.

Not the campaign game.

The game that’s turned a quiet brainiac named Ken Jennings into America’s newest television hero: “Jeopardy!”

Monday, the mild-mannered software designer from Salt Lake City returns to the classic quiz show to defend his title as the longest-running, highest-earning, best-ratings-getting player ever on the syndicated program.

Without eating maggots, without sifting through a bevy of bachelorettes or warbling a Barry Manilow tune in front of Simon Cowell, Jennings, 30, has won $1.3 million (so far) and become a star.

He’s heralded on Internet blogs: “There are now three constants in life: death, taxes and Ken Jennings,” Jason Kottke (Kottke.org) recently wrote under the heading “The Cult of Ken Jennings.”

He’s been given a catchy celebrity nickname: KenJen.

There are even T-shirts with his image being peddled on eBay.

When “Jeopardy! faded into its summer reruns in late July, Jennings had sailed through 38 consecutive games, beating 76 opponents with more than 1,300 correct responses in more than 450 categories.

Of course, there have been impressive “Jeopardy! champions before. New York City transit cop Frank Spangenberg won more than $102,597 in 1990. Computer consultant Leszek Pawlowicz won $75,400 in 1992. But in the past, “Jeopardy! contestants played for lower sums and were required to leave the show after winning five consecutive games. Some were invited back for the limited-run Tournament of Champions.

But at the beginning of last season (the program’s 20th), producers changed the rules, allowing players to remain for as long as they kept winning. Tom Walsh set the record with seven consecutive victories.

Then came Jennings.

He started his 38-game streak on June 2, winning $37,201 in a mere half-hour, and he just kept hitting home runs. On July 23, the last show before the break, Jennings amassed $75,000, setting a one-day earnings record. The old record was $52,000 achieved by Brian Weikle in 2003.

The KenJen run also made the show’s ratings rocket.

Viewership rose from 9.6 million in June to a whopping 15 million in July, beating even the perennial game-show ratings champ “Wheel of Fortune,” which had 12.4 million, according to Nielsen Media Research.

“He had an enormous impact on a show that didn’t even need help,” said Marc Berman, a columnist for mediaweek.com. “He was just an unexpected bonus. By the end of the season, ‘Jeopardy!’ was beating out most shows on network television.”