NEW YORK (AP) – Former President JD Vance's Donald Trump Pick as his running mate has led to a surge in sales of “Hillbilly Elegy,” his best-selling memoir that came out in 2016.

A HarperCollins spokesman told The Associated Press that more than 650,000 copies have been sold since Trump's July 15 announcement. The total includes physical books, audiobooks and e-books.

“We are printing hundreds of thousands of copies to meet demand from our retail partners,” the publisher announced Thursday.

Vance's book had already sold more than 3 million copies before Trump chose him for the Republican ticket. “Hillbilly Elegy,” which Ron Howard adapted into a feature film for release in 2020, tells the story of Vance's childhood in Ohio and his family's roots in rural Kentucky. After Trump's stunning victory in 2016, the book was widely cited as essential reading for Trump opponents trying to understand his appeal to working-class whites, though some critics criticized it as a narrow and misleading portrait of Appalachia and poverty in the US.