Some of the country’s most prominent Catholic conservative thought leaders released a letter Monday slamming Republican front-runner Donald Trump, saying there is no evidence the mogul shares their values on abortion and religious freedom and that his presidential primary campaign “promises only the further degradation of our politics and our culture.”

“His campaign has already driven our politics down to new levels of vulgarity. His appeals to racial and ethnic fears and prejudice are offensive to any genuinely Catholic sensibility,” read the letter, which ran in the conservative journal National Review. “We understand that many good people, including Catholics, have been attracted to the Trump campaign because the candidate speaks to issues of legitimate and genuine concern…We urge our fellow Catholics and all our fellow citizens to consider, however, that there are candidates for the Republican nomination who are far more likely than Mr. Trump to address these concerns, and who do not exhibit his vulgarity, oafishness, shocking ignorance, and — we do not hesitate to use the word — demagoguery.”

The letter was signed by some of the best-known Catholic conservative intellectuals, including Princeton University Prof. Robert George, papal biographer George Weigel and Nina Shea of the Hudson Institute think tank.

The letter was the first major effort by Catholic conservatives to publicly address the tumultuous presidential campaign. While clergy are limited in their ability to publicly address politics, U.S. bishops have been particularly quiet this campaign season, though Pope Francis made international news last month when he was asked about Trump and said someone who advocates building walls “is not Christian.” A spokesman later said the pope didn’t intend to single out the American businessman.

In a Pew Research Center poll in January, 30 percent of Catholics said Trump would be a “good or great” president, compared with 52 percent of white evangelicals and 39 percent of white Mainline Protestants. Fifty-three percent of Catholics said he would be “poor or terrible” — the highest percentage of any Christian group aside from black Protestants. Sixty-eight percent of black Protestants said Trump would be poor or terrible as president.

Chad Pecknold, a Catholic University theologian who signed the letter, said Monday that signers are concerned that Trump voters “aren’t signing up for our issues” — religious freedom, traditional marriage, limited government and “legal protection for unborn children, the physically disabled and cognitively handicapped, the frail elderly,” the letter said.

“The question is, how do you reach the Catholic Trump voter?” Pecknold said. The recent death of Supreme Court Justice Antonin Scalia, he said, has focused Catholic conservatives even more on a candidate who they see as a genuine conservative.

In his circles, Pecknold said, Catholic conservatives are split between Sens. Marco Rubio and Ted Cruz. One difference, he said, are those who are affected by the call of Catholic leaders — notably the pope — and Catholic teaching for a more welcoming, “humane approach on immigration,” he said.  Catholics who are “more hard line” prefer Cruz, he said.

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