Different media accounts during the recent Covid-19 pandemic have mentioned an upswing in horse racing gambling thanks to a decline in other forms of wagering at casinos and with sports gambling. This paper examines gambling trends across the US before and during the pandemic for these forms in gambling as well as lotteries. Horse racing wagering did see an increase, but not as dramatically as one would expect.
Lambert, Thomas E., "Did Covid Benefit or Harm Horse Racing Wagering? A Comparison of Trends" (2021). Faculty Scholarship. 527.