MIAMI - AUGUST 1: A motorist waves a Cuban flag while cruising down the famous Calle Ocho in the Little Havana neighborhood August 1, 2006 in Miami, Florida. Cuban Americans were celebrating the news that Fidel Castro had turned over power to his younger brother, Raul Castro, while he undergoes medical treatment for intestinal bleeding. (Photo by Chip Somodevilla/Getty Images)

Republicans have been fighting to regain lost ground with Latino voters after Mitt Romney's unsuccessful presidential campaign. A new report shows the problem may be even bigger than they imagined.

An analysis of survey data by the Pew Research Center published Tuesday shows that the Cuban population in the U.S., once known for its staunch support of the GOP, is shifting towards the Democratic Party.

Throughout the years, while Latinos across the nation leaned Democrat, according to Gallup, Cubans remained among the most conservative within the group. But as of 2013, only 47 percent of registered Cuban voters say they identify with the Republican Party, down sharply from the 64 percent who said they leaned towards the GOP a decade ago, according to Pew.

The difference between those who identified as Democrats in 2002 and now is also drastic. Twelve years ago only 22 percent of the Cuban population in the U.S. identified with the liberal party while today the number has doubled to 44 percent.

Pew attributes this partially to the coming-of-age of U.S. born Cubans, who tend to be more liberal than their parents.

The shift is also explained by generational differences. Those who came in the 1960s were largely fleeing from the Communist dictatorship installed by Fidel Castro, and their opposition to Castro hardened into a reliably conservative political mindset.

By contrast, the generation of Cuban immigrants who arrived since the 1990s tend to be more liberal than the 1960s exile generation. Post-1990 arrivals now make up more than half of Cuban immigrants, according to Pew.

"Cuban-Americans, when we first came to America said, 'Look, Republicans are against Communism. They're for liberty. They're for freedom. We're with them,'" Al Cardenas, former head of the Florida Republican Party told CBN News.

In 2004, President George W. Bush won 78 percent of the Cuban vote in Florida, giving him the overall victory with Hispanics in the state with 56 percent. Eight years later in 2012 the Cuban vote in the state was split with 49 percent supporting President Barack Obama and 47 percent supporting Republican candidate Mitt Romney, according to Pew.