He rode in his first race at age 14. It was a record not broken until
Willie Shoemaker exceeded it in 1952. In his career, more than half the time his horse finished "in the money". He set a record by riding eight consecutive winners, over a two-day period at
Benning Race Track. He also won the
Travers Stakes,
Alabama Stakes,
Champagne Stakes,
Saratoga Special Stakes, and
Brooklyn Handicap. Writer Sam Elias described Miller as “a better rider than
Tod Sloan.” He rode at times for
James R. Keene’s stable, Newcastle Stables. Most of his career, he was managed by
"Sunny Jim" Fitzimmons. His career ended in the United States after he gained weight as a late teenager. He grew to 5’ 8.5” and 160 pounds. In 1909 and 1910, he rode primarily in
Australia and
Europe where weight restrictions were less stringent. ==Honors==