Gingrich lines up strongly with the political right's positions on social and fiscal issues. But some Republicans see him as a figure from the past, and he is in his third marriage after two messy divorces.
As a Georgia congressman in 1994, Gingrich co-authored the GOP's "Contract with America," leading a resurgence that brought Republicans a House majority for the first time in four decades. Gingrich also has been a college professor and author.
He is married with two daughters.
— Associated Press
Sheldon Adelson, whose family largely bankrolled the revival of the candidate's Republican presidential bid, stands apart from other barons on the Las Vegas Strip.