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Marco Rubio has something in common with Mitt Romney: their religion.

The young tea party hero most likely on Mitt Romney's short list of potential running mates was baptized into the Mormon church when he was 8 and "remained active in the faith for a number of years," attending LDS youth groups and walking to church most Sundays because his mother didn't drive, the Internet meme and news site BuzzFeed reports.

Rubio left Mormonism to become a Catholic "a few years later," and he got his first Communion when he was 13, in 1984, the Florida senator's spokesman told the website.

Romney's faith has occasionally been a topic of discussion in the Republican primary. Many Americans are unfamiliar with Mormonism, a Christian religion that has been called a cult by a pastor who endorsed Rick Perry and even by Romney's chief rival, Rick Santorum.

"Would the potential attraction to Mormonism by simply having a Mormon in the White House threaten traditional Christianity by leading more Americans to a church that some Christians believe misleadingly calls itself Christian, is an active missionary church, and a dangerous cult?" Santorum wrote in a 2007 newspaper column.

The revelation also muddies the prospects of Rubio's getting the VP nod from Romney. Though many conservatives love Rubio - he overwhelmingly won a straw poll for vice presidential nominee at an annual gathering of conservatives in Washington this month - the bottom of the ticket is often used for balancing a variety of attributes.

BuzzFeed says that its questions to Rubio's aides about his religion "appear to have sent them into frantic damage-control mode." The Miami Herald published a blog mentioning Rubio's Mormon roots just before Rubio's spokesman called the website to confirm the story. The spokesman said Rubio plans to write about his Mormon faith in a book.