Billionaire casino mogul Sheldon Adelson and his wife, Miriam, have donated another $10 million to a super PAC supporting Republican presidential candidate Mitt Romney.

Adelson, 79, chairman of Las Vegas Sands Corp, has emerged as one of the largest patrons of Republican causes, donating at least $47 million.

The Adelsons gave $5 million each to the pro-Romney Super PAC Restore Our Future, accounting for about half of the fund’s cash raised from October 1 through 17, according to Federal Election Commission filings released last week. The filings are the last disclosures before the November 6 elections.

The Adelsons said they made their second donation to the super PAC to “help level the playing field”, as late last month, billionaire George Soros pledged $1 million to a Super PAC supporting President Obama.

Restore Our Future launched a major swing-state ad campaign last week, buying almost $18 million worth of commercial time in 10 states.

Adelson told Politico last month that he planned to spend up to $100 million, or “whatever it takes,” to defeat Obama.

Adelson hosted a fund-raiser for Romney and joined the Republican nominee during his trip to Israel in July.

Earlier this month, the Adelsons gave an additional $500,000 to the Patriot Prosperity super PAC supporting Rabbi Shmuley Boteach’s bid for Congress in New Jersey’s 9th Congressional District.