Just three years ago, Sheldon Adelson’s casino empire was deep in debt and facing default. But the Sands owner has bounced back, largely by investing in casinos in Macau, the booming casino market in China.

Now Adelson is reshaping the presidential race by giving $21 million to a Super PAC that is supporting Newt Gingrich and threatening to spend as much as $100 million in campaign contributions to try and unseat President Obama.

Not many people had even heard of Adelson until recently. He has largely operated behind the scenes. But at 78 years old, the billionaire has stepped into the spotlight with large campaign donations. Forbes magazine has a largely positive profile of Adelson that is worth reading to see how he operates.