In this Aug. 23, 2011 file photo, Sen. Marco Rubio, R-Fla. speaks in Simi Valley, Calif. Rubio’s push for a Republican version of immigration legislation could be the answer to GOP election-year prayers. The telegenic son of Cuban exiles and potential vice presidential pick is putting together a bill that would allow young illegal immigrants to study and work in the United States but still deny them citizenship. (AP Photo/Jae C. Hong, File)

Florida U.S. Sen. Marco Rubio has become known for his family’s immigrant story. But an unauthorized biography is calling attention to the undocumented status of Rubio’s maternal grandfather.

The book, “The Rise of Marco Rubio,” published by Simon & Schuster, is set for release June 19. It says that Rubio’s maternal grandfather entered the country without a visa and was to be deported.

The biography on the junior senator, written by Manuel Roig-Franzia, says that Rubio’s maternal grandfather, Pedro Victor García, was ordered to leave from Florida because he flew in from Cuba without a visa, reports Politico.

The author conducted more than 100 interviews in researching Rubio “and located a scratchy recording of the grandfather’s immigration hearing,” according to Politico.

The book describes Rubio as the “crown prince” of the tea party movement and “the Michael Jordan of Republican politics.” It documents his rise in American politics and traces his immigrant story through his parents’ journey out of Cuba for a better life in Miami in the 1950s, a few years before Castro came to power. Rubio was born a U.S. citizen in Miami and later studied law.

Rubio has gained popularity among Republicans, being dubbed the party’s “golden boy” and a possible running mate for presumed GOP presidential nominee Mitt Romney. Rubio was sworn into public office in 2000, becoming the youngest person and first Hispanic in the Florida House of Representatives. He was elected to the U.S. Senate in 2010.

After headlines about a Florida high school valedictorian facing deportation, Rubio announced he was working on a Republican version to the DREAM Act. To prevent “chain migration,” his version would not offer a pathway to citizenship.

More questions surrounding Rubio’s stance on illegal immigration will surely surface with the release of the unauthorized biography come June 19.

Read it at Politico