Billionaire Sheldon Adelson made a $1.2 million donation to a super PAC linked with Sen. John McCain (R-Ariz.), according to ProPublica.
{mosads}Adelson made the donation to the Arizona Grassroots Action PAC, which is aligned with the Arizona senator, in mid-August.
Republican donors Paul Singer and Sam Fox also made sizable donations to the super PAC, giving $250,000 each.
A recent poll by Emerson College showed McCain leading the Senate race in Arizona, up by 16 points over his Democratic challenger, Rep. Ann Kirkpatrick.
Adelson has been a major donor to Republican candidates up and down the ballot. He spent about $100 million on Republicans in 2012.
He endorsed Republican presidential nominee Donald Trump in May but has been slow to fork over the millions of dollars he has given to presidential candidates in the past. It was reported last month that he planned to donate $5 million to support Trump, although it’s not clear if the money has reached the campaign yet.
He has this cycle focused his deep pockets on helping down-ballot Republicans, especially in the Senate, which would be easier for Democrats to reclaim.
In August, Adelson and his wife gave $20 million to the Senate Leadership Fund, a super PAC linked with Majority Leader Mitch McConnell (R-Ky.). The fund is working to preserve and expand the chamber’s GOP majority.
He has also given $1.5 million to a group helping Republican Sen. Kelly Ayotte hold her New Hampshire seat.
Adelson reportedly planned to spend some $45 million on the 2016 races.