The latest news reports say that Newt Gingrich plans to drop his roller coaster of a presidential bid next week but Sunlight's Follow the Unlimited Money tracker suggests that the former House speaker's biggest money backers may already have pulled the plug.

Winning Our Future, the pro-Gingrich group that has been almost entirely funded by the family of gambling mogul Sheldon Adelson, made it's last independent expenditure almost a month ago in the Wisconsin primary, the tracker shows.  That means the committee didn't play in Delaware, the state where Gingrich vowed to make his last stand — and which turned into his Waterloo.

Of the nearly $24 million Winning Our Future raised since its creation last year, $21.5 million was donated by Adelson and members of his family. The last donation — $5 million from Adelson's wife, Miriam, came on March 21. 

The Adelsons may be switching their loyalties from a former GOP House leader to the current one: they recently kicked a combined $5 million into the Congressional Leadership Fund, a super PAC linked to House Speaker John Boehner, R-Ohio.