who has won the most money on a game show
Thom McKee
American game show winnings records
Teddy Nadler of "The $64,000 Challenge", the highest-scoring contestant of the 1950s era, was not surpassed until 1980, when Thom McKee won $312,700 on "Tic-Tac-Dough." 
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American game show winnings records [SEP] Introduction
Teddy Nadler of "The $64,000 Challenge", the highest-scoring contestant of the 1950s era, was not surpassed until 1980, when Thom McKee won $312,700 on "Tic-Tac-Dough." Between 1999 and 2001, during a brief boom in high-stakes game shows, the record was broken six times. Both the 1955–1958 and 1999–2001 eras of rapidly set and broken records were driven primarily by one-upmanship between the networks each trying to secure bragging rights and ratings by inflating their prize offerings, rather than the merits of the contestants themselves. American daytime television has historically had smaller prize budgets for game shows that air in that daypart.