NEW YORK — Miriam Adelson, wife of casino and hotel magnate Sheldon Adelson, has donated $5 million to a group supporting Newt Gingrich for the Republican presidential nomination.

The donation matches one given earlier last month by her husband to Winning Our Future, an independent committee, or super PAC, that is run by former Gingrich associates, according to a report in the Las Vegas Review-Journal, citing GOP sources. Major media outlets confirmed the report Jan. 23.

The funding came just days after Gingrich scored an upset in the South Carolina primary and ahead of a key primary in Florida on Jan. 31.

Super PACs can raise unlimited sums from corporations, unions and other groups, as well as individuals, and indirectly support a political candidate. They cannot by law co-ordinate with the candidate’s official campaign.

Miriam Adelson, an Israeli by birth, runs two non-profit drug treatment and research centers in Nevada and Israel.

Sheldon Adelson, chairman and CEO of the Las Vegas Sands Corp., is worth more than $21 billion, according to Forbes magazine. He is a major giver to Birthright Israel, which provides free 10-day trips to Israel for Jews aged 18 to 26.