Sen. Rob Portman says he has donated money he received from Las Vegas billionaire Steve Wynn to charities working to stem human sex-trafficking in Ohio.

In a statement Monday to The Associated Press, Portman spokeswoman Emily Benevides says the Ohio Republican “donated the money to a number of charities across Ohio that he’s worked closely with.”

Wynn resigned as the Republican National Committee’s finance chairman Saturday after allegations of sexual misconduct were published Friday in The Wall Street Journal.

Republican Sens. Susan Collins of Maine and Lindsey Graham of South Carolina have urged Republicans who have received money from Wynn to return them.

Portman is among several Republicans in the Senate to receive money from Wynn, a prolific Republican donor over the past decade who has also previously backed Democrats.