Sheldon Adelson, a billionaire casino boss, who was one of Newt Gingrich’s top backers, has become Mitt Romney’s largest donor.

Sheldon Adelson has handed a $10 million donation to Restore Our Future, a super PAC devoted to the election campaign of the former Massachusetts governor, according to the Wall Street Journal.

While the gift could make a big difference to Mitt Romney’s election hopes, it is little more than a drop in the ocean for Sheldon Adelson, whose fortune is believed to add up to $20 billion.

Sheldon Adelson, a billionaire casino boss, who was one of Newt Gingrich's top backers, has become Mitt Romney's largest donor

Sheldon Adelson made his fortune with Las Vegas Sands, which owns enormous casinos in Macau and Singapore as well as in Las Vegas.

The tycoon was by far the biggest supporter of Newt Gingrich’s campaign for the Republican presidential nomination, propping it up almost single-handedly with around $21 million worth of funding.

Sheldon Adelson, who appears to be primarily motivated by support for Israel, has apparently pledged to give a total of $100 million to Republicans this election year.