"There is a broader fascination with Obama, from conservatives who really hate him as well as liberals who deeply admire what he did," says presidential historian Julian Zelizer.

If you believe Esther Newberg, co-head of ICM Partners' publishing unit, former President Barack Obama is about to come into some serious cash — $20 million or more. "There's no doubt Obama's memoir will go for more than any president's has ever gone," she predicts.

The bar is high. George W. Bush got $7 million for 2010's Decision Points (which sold more than 2.6 million copies), and Bill Clinton got a whopping $15 million — a presidential record — for 2001's My Life (sales of 2.2 million). Princeton University presidential historian Julian Zelizer predicts Obama's advance and sales will top both: "There is broader fascination with Obama, from conservatives who really hate him as well as liberals who deeply admire what he did."

Obama, 55, who likely will be repped by Washington lawyer Bob Barnett, recently told senior adviser turned CNN commentator David Axelrod that the book is his top priority. And he hired Cody Keenan, former White House director of speechwriting, to help. While every major publisher likely will bid, Random House, which published Obama's 1995 memoir Dreams of My Father and 2008 campaign book The Audacity of Hope (combined sales: 5 million), as well as both the Clinton and Bush books, has the inside track.

One wild card: Obama might find a rival in wife Michelle, whom Newberg predicts will "easily" surpass the $8 million Hillary Clinton got in 2000 for her memoir. Says the University of Virginia's Brian Balogh, who co-hosts the popular history podcast Backstory: "We haven't heard as much from [Michelle], and he won't be running for president, whereas she …"

A version of this story first appeared in the Feb. 3 issue of The Hollywood Reporter magazine. To receive the magazine, click here to subscribe.