It is very hard now to get to deduct losses. You can't deduct it directly from the winnings.
See Can I Deduct gambling losses?
https://ttlc.intuit.com/community/credits-and-deductions/help/can-i-deduct-my-gambling-losses/00/258...
Gambling Losses are an itemized deduction and you need to itemize on schedule A to use them. So if your Standard Deduction is more they won't be used. And since the Standard Deduction has increased a lot more people will be taking the Standard Deduction.