You can almost hear the political world asking, “Newt who?”

Newt Gingrich, former House Speaker and a major Washington figure for decades, has been pushed to the fringes of presidential campaign discourse.

Although he’s still formally a candidate for the GOP’s 2012 nomination, he describes Mitt Romney as “far and away the most likely” GOP nominee – a fact made all-but-certain by Rick Santorum’s dropping out this week. Mr. Santorum had been Romney’s last remaining serious challenger.

With $4.5 million in debt, the Gingrich campaign organization has been operating on a shoestring as his principal financial angel, billionaire casino owner Sheldon Adelson, began moving toward the Romney campaign.

“It appears as though he’s at the end of his line,” Adelson said recently. “Because, I mean, mathematically, he can’t get anywhere near the numbers, and it’s unlikely to be a brokered convention.”