how many lengths did secretariat win the belmont stakes
31 lengths.
Belmont Stakes
 At the finish, he won by 31 lengths, breaking the margin-of-victory record set by Triple Crown winner Count Fleet in 1943 of 25 lengths.
He won by 31 lengths. 31 lengths 31 lengths
Secretariat (horse) Secretariat (horse) Secretariat (horse)
Introduction Introduction Introduction
Secretariat (March 30, 1970 – October 4, 1989) was an American Thoroughbred racehorse who, in 1973, became the first Triple Crown winner in 25 years. His record-breaking victory in the Belmont Stakes, which he won by 31 lengths, is widely regarded as one of the greatest races in history.  31 lengths His record-breaking victory in the Belmont Stakes, which he won by 31 lengths, is widely regarded as one of the greatest races in history
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Secretariat (horse) [SEP] Belmont Stakes
Secretariat, however, did not falter. Turcotte said, "This horse really paced himself. He is smart: I think he knew he was going miles, I never pushed him." In the stretch, Secretariat opened a lead of almost of a mile on the rest of the field. At the finish, he won by 31 lengths, breaking the margin-of-victory record set by Triple Crown winner Count Fleet in 1943 of 25 lengths. CBS Television announcer Chic Anderson described the horse's pace in a famous commentary: The time for the race was not only a record, it was the fastest miles on dirt in history, 2:24 flat, breaking by more than two seconds the track and stakes record of 2:26 set 16 years earlier by Gallant Man.