No matter how Newt Gingrich fares in Saturday’s Republican presidential primary here, he can thank his friends Las Vegas casino tycoon Sheldon Adelson and the operatives at Winning the Future, the super PAC that has leveled the media playing field for him since Adelson, a billionaire, wrote a check for $5 million to the organization. Gingrich’s candidacy was hanging by a thread after woeful finishes in Iowa and New Hampshire, caused in part by negative ads financed by a super PAC allied with Mitt Romney . As dramatically as super PAC money has whipsawed the Gingrich campaign, it also threatens to return the making of the president to a pre-Watergate free-for-all of big money chasing big returns at the ballot box.