Reporting your gambling winnings and losses on Schedule C as a professional gambler might reduce your MAGI for Roth IRA purposes because the losses on Schedule C will reduce your AGI. The only way to see whether it would allow you to make a Roth IRA contribution is to do a trial tax return. And note that you cannot claim a net loss from gambling. Even on Schedule C your losses cannot exceed your winnings.
But to file as a professional gambler, gambling has to be your primary occupation. If you have significant income from a job or another business, the IRS is likely to say that you are not a professional gambler. Also, check with a local tax professional concerning your state's rules about professional gamblers. Each state has different rules. The state might not allow you to file as a professional gambler, even if the IRS does.
Thank you so much for your response. I did lose close to the amount I won. One last question on Schedule C can I deduct expenses above my losses? Meaning if my losses cancel out my wins can I still deducted gambling Expenses like travel, hotel food. on Schedule C?
Travel and other expenses are treated as additional gambling losses, and are subject to the same rule. Your total losses, including expenses, cannot exceed your winnings. As a professional gambler you cannot show a net loss on Schedule C. The most the expenses can do is reduce your net gambling income to zero.
(The law on expenses was changed starting in 2018.)
Note that you have conflicting goals in trying to be able to make a Roth IRA contribution. In order to contribute to a Roth IRA you have to have "compensation," and the amount you can contribute is limited to the amount of your compensation. A net profit on Schedule C is considered compensation, but if your losses and expenses reduce the net to zero or very little, then that doesn't give you the compensation that you need in order to make a Roth IRA contribution. And if you have significant other compensation, such as from a job, claiming to be a professional gambler is questionable.