He has a way to go though, if he wants to get the all time high. The following guy set the record for consecutive winning days...
Ken Jennings: $3,270,700. Ken Jennings is arguably the most famous "Jeopardy!" contestant in the show's history, as he holds the record for the longest winning streak, with a 74-game streak in 2004. In total, he has won $3,270,700 in prize money.
And then there is this guy with highest total, but over a period of years...
Brad Rutter is the highest earning contestant on "Jeopardy!" ever: he's made around $4,385,702 over 14 years. His first, five-day streak earned him $55,102, but winning the Tournament of Champions ($250k), the Ultimate Tournament of Champions ($2 million), the Masters Tournament ($1 million), and the Battle of the Decades ($1 million) bumped his earnings significantly.