Park Romney says some pretty wild things.

Mormonism, he claims, is "an insidious contemporary fraud."

The Church of Jesus Christ of Latter-day Saints is "an American cult," he professes.

The Mormon prophet Joseph Smith, he asserts, "declared himself king, and ordered the destruction of a private printing enterprise that was about to publish revelations about his personal indiscretions."

Were you to come across a man articulating such views on a street corner, you probably would give him a wide berth and look over your shoulder to make sure he wasn't following you.

But Park Romney, apostate Mormon, is no street-corner eccentric. He is Mitt Romney's second cousin – church documents, and archival research done by the Washington Post's Lucy Shackelford, trace Park's lineage to Miles Park Romney, who is also Mitt's great-grandfather – and he has a website criticizing his famous relative.

The two men have never met (Miles Park Romney had 30 children, which means Mitt Romney has scores of cousins), and, based on what Park has been saying about his cousin, he's not likely to be getting a dinner invitation to Mitt's anytime soon.

"Gov. Romney has never heard of this person, and he doesn't know him," Romney campaign spokeswoman Andrea Saul said.

Every family has a crazy uncle. The difference is, when you're running for office and you become a famous name, your relatives' surname becomes famous too – often in unwelcome ways.

As Meghan McCain can tell you, sharing a famous politician's surname can be good for business. Billy Carter used his famous name to do work for Libya, when he wasn't endorsing Billy Beer. A man claiming to be a half-brother of Barack Obama acknowledged he was a "stranger" to the American politician, but that didn't stop him from becoming a media sensation because he lived in a corrugated-metal shack in Kenya. Patti Davis clashed with estranged dad Ronald Reagan's politics and later posed in the nude.

In most cases, the family antics are more embarrassing than politically damaging. There were Neil Bush's S&L problems, Roger Clinton's cocaine and Hugh Rodham's role in pardons. Lyndon Johnson reportedly kept his hard-drinking brother under Secret Service surveillance. Jacqueline Kennedy's aunt and cousin hoarded cats, becoming the subject of a movie. Richard Nixon's brother Donald took a bailout from Howard Hughes for his burger restaurant.

The tradition continues with the Obamas. When Onyango Obama was charged with drunken driving outside Boston last year, it became national news, even though the president had no contact with his long-lost Uncle Omar. Among those calling publicly for the man's deportation: Mitt Romney. Likewise, Zeituni Onyango's immigration case – unknown to her nephew Barack – became big news days before his election in 2008.

Park Romney, who declined to comment for this column, appears to be on this path. He wrote a book last year detailing his views of the Mormon Church that is available on Amazon. The gay rights group Pride in Utah has embraced him as a spokesman ("Mitt Romney's Cousin Speaks Out").

This isn't necessarily bad news for Mitt Romney. For a candidate who comes across too often as programmed, the emergence of a "crazy cousin" might remind voters that Romney is just like the rest of us.

Some might argue that the best response to Park Romney's anti-Mormonism is to ignore him. I have no sympathy for his message; I find his claim that Mitt Romney's policy positions would be influenced by "obedience to the leadership of the Mormon Church" to be preposterous. And I think some of the other topics on his website (from sleep apnea to the "Votaries of the Lotus Sutra") suggest that Park Romney is rather quirky.

But we don't ignore the birther movement, anti-Semites, tea-party racists or people who encourage violence on the airwaves, and I don't think Park Romney, who shares the views of a large community of apostate Mormons, should be ignored either.

His sentiments, unfortunately, are not fringe views: As my colleague Chuck Lane pointed out recently, about one in five Americans, Democrats and Republicans alike, tell Gallup they wouldn't vote for a Mormon presidential candidate from their own party. And now Newt Gingrich is flirting with that segment of the population on the stump: He's calling for a defense of "our religions" and accusing Mitt Romney of discriminating against Catholics and Jews.

For that reason, Park Romney's use of the family name is part of something darker than Billy's beer. The anti-Mormonism he represents should be examined in the light of day.

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Dana Milbank is distributed by the Washington Post Writers Group.

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