The head of the party, Jim Greer, was forced to resign following revelations he and his second-in-command charged $1.5 million on party credit cards, much of it on luxurious hotels, fancy restaurants, chauffeured sedans and lavish entertaining. Greer's trial is set to start July 30, just ahead of the Republican convention, and many Republican observers anticipate he will detail unethical use of party money by other high-ranking GOP officials.
Rubio spent more than $100,000 on the party card between 2006 and 2008, paying off about $16,000 in personal expenses and claiming the rest as official party business. His records from 2005, when he was lobbying to become Florida House speaker, never were released. When asked about using the party card for personal expenses, Rubio has said he sometimes just pulled the wrong card out of his wallet and he has called it a "lesson learned."
He also has had to answer criticism for how he spent money donated to two political committees he formed - including payments to relatives. He has acknowledged the bookkeeping for at least one of the accounts was sloppy.
Then there's his family's background.
Rubio long claimed his parents fled Fidel Castro's rule. But it was recently disclosed that they arrived several years before Castro took power, although they quickly embraced the Cuban exile community as Castro turned toward communism. Rubio has said the dates he gave were based on his parents' recollections.
There's another part of Rubio's upbringing that long had gone undisclosed, and the revelation is one that could turn off evangelicals who make up the base of the GOP.
Rubio was baptized as Mormon when his family lived for a few years in Las Vegas, thanks to the influence of cousins who belonged to The Church of Jesus Christ of Latter-day Saints. Rubio returned to the Catholic Church as a young teen, and as an adult he has also frequently attended Baptist services.
When it comes to the vice presidency, Rubio's greatest liability may be one only time can resolve.
"I suspect that the Romney campaign is going to pick someone who is viewed as unquestionably qualified for the office," said Schmidt, who was intimately involved in McCain's selection of Sarah Palin. "To the extent that (Rubio's) in his first term, he's in the first two years of his term and he's 40 years old probably doesn't help him."
Farrington reported from Tallahassee, Fla.
Rubio biography: http://www.rubio.senate.gov/public/index.cfm/biography
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