The win, in a starter allowance against five rivals, also was the 21st straight for the 5-year-old gelding, trained by David Wells.
The record for wins in a calendar year was held jointly by Citation, in 1948 when he won the Triple Crown, and by Roseben, a Hall of Fame honoree who turned the trick in 1905.
Rapid Redux, with jockey J.D. Acosta, was reluctant to load into the starting gate for the Tuesday's 1 1/16-mile race but went quickly to the lead and did not let a rival get close enough to threaten until the very end. He finished in 1:45.08 and won by a half-length over Awesome Rhythm, with No Brakes finishing third.
"It's an incredible feat of luck and incredible skill by the horse," owner David Cole said. "My dad talked about Citation all the time and it's amazing -- here we are at 19 with Citation. There is no way you could ever imagine claiming a horse for $6,000 that would be mentioned in the same breath as Citation. It is more than a million to one. I know that and do not take it for granted."
Cole and Wells claimed Rapid Redux for $6,250 on Oct. 13, 2010, at Penn National. Since that race, he has won 22 times in 23 starts at seven tracks over distances ranging from 5 furlongs to 1 1/8 miles and earned $256,384.
Wells said he might look for one more start this month to give Rapid Redux the chance to break the single-year record. But he has resisted the temptation to look for richer purses at higher levels of racing.
"The reason we kept him sound is we picked our spots really well -- keeping him in the $5,000 starters. You run him in an allowance race or a stakes, he is tore up. We have turned down $35,000 a couple of times but he is not going to win for more than that. Why not let him go out on top? That's what I want to do."